* Customization for make targets in build and test phases for AutotoolsPackage

* Updated Blitz++ to use customized make build and test targets

* Removed flake8 error

* Removed make test customization, added make install customization, need to figure out issues with multiple make targets

* Changed build_targets and install_targets to normal attributes

* MakefilePackage: changed build_args and install_args for consistency with #2464
openblas: derives from MakefilePackage

* MakefilePackage: changed default edit behavior

Changes any to a string to avoid <built-in function any> being
incorrectly added to target in compilers.yaml.

Fixes issue #2578

* Better cxx11/14 flags for GNU/Clang/Intel

- GCC 4.8 only supports -std=c++1y for C++14
- Use CMake's rules for AppleClang to set cxx11 and cxx14 flags based on
  Apple Xcode/LLVM version
- Use CMake's rules for Intel to add support for cxx14 flags based on
  Intel version.

* Add cxx17_flag property

Implement property in compiler for c++17 as per those for c++11/14.
Add concrete support for GNU/Clang:

- Return -std=c++1z for GCC 5 and above per GCC documentation
- Return -std=c++1z for Clang 3.5 and above per Clang documentation
- Return -std=c++1z for Apple LLVM 6.1 and above per CMake's rules

* Update `spack setup` and `spack graph` to be consistent with c557e765 and 9347f869.  Fixes #2316.

* Added another "fix" necessary to make `spack setup` work.

* Added another "fix" necessary to make `spack setup` work. (reverted from commit 7f0d3ecb38c97ec00491d7cd66b4266e3018b1ca)

* Add freetype dependency on bzip2

* Switch package with an install method for the docs

* Add documentation for repositories and namespaces.

* Update and extend repository documentation per review.

- Also add `-N` argument for `spack spec`

The advanced [Uninstalling Packages](spack.readthedocs.io/en/latest/tutorial_sc16_spack_basics.html#uninstalling-packages) via hash has a couple missing `.. code-block:: console` directives ;)

I have no idea what branch to direct this to though...

* clang: do xcode mockup iff requested by a package

* add a note

* add pkg to setup_custom_environment() and decide whether or not to use mockup XCode there based on the package

* Make targets an attribute of compilers, similar to OS. Allows users to use `spack compiler find` to add compilers for the same platform/os but different targets when spack is installed on a file system mounted on machines with different targets.

* Changed get_compilers() method to treat old compilers with no target as target='any'

* flake8 changes

* Address change requests for comments/code clarity

* Add support for parsing R-XML URL versions.

* Better url-parse debug output.

- just print the debug stuff all the time.

* fix R-XML versions.

* fix for  bluegene-q platform

* change powerpc to ppc64

* change CNK to cnk

Fixes #2306

Any dependency explicitly mentioned in a spec string ended up with the
build and link deptypes unconditionally. This fixes dependency
resolution to ensure that packages which are mentioned in the spec
string have their deptypes determined by the dependency information
in the package.py files. For example if a package has cmake as a build
dependency, and cmake is mentioned as a dependency in the spec string
for the package, then it ends up with just the build deptype.

Packages built targeting a backend may depend on packages like cmake
which can be built against the frontend. With this commit, any build
dependency or child of a build dependency will target the frontend by
default. In compiler concretization when packages copy compilers from
nearby packages, build dependencies use compiler information from
other build dependencies, and link dependencies avoid using compiler
information from build dependencies.

* Use JSON for the database instead of YAML.

- JSON is much faster than YAML *and* can preserve ordered keys.
  - 170x+ faster than Python YAML when using unordered dicts
  - 55x faster than Python YAML (both using OrderedDicts)
  - 8x faster than C YAML (with OrderedDicts)

- JSON is built into Python, unlike C YAML, so doesn't add a dependency.
- Don't need human readability for the package database.
- JSON requires no major changes to the code -- same object model as YAML.
- add to_json, from_json methods to spec.

* Add tests to ensure JSON and YAML don't need to be ordered in DB.

* Write index.json first time it's not found instead of requiring reindex.

* flake8 bug.

* Allow spack create to handle packages with period in name

* Update tests to handle new package name detection scheme

* Added some notes about how multiarch detection could be fixed.

* Implemented a preliminary version of the "spack.spec.ArchSpec" class.

* Updated the "spack.spec.Spec" class to use "ArchSpec" instead of "Arch".

* Fixed a number of small bugs in the "spack.spec.ArchSpec" class.

* Fixed the 'Concretizer.concretize_architecture' method so that it uses the new architecture specs.

* Updated the package class to properly use arch specs.
Removed a number of unused architecture functions.

* Fixed up a number of bugs that were causing the regression tests to fail.
Added a couple of additional regression tests related to architecture parsing/specification.
Fixed a few bugs with setting reserved os/target values on "ArchSpec" objects.
Removed a number of unnecessary functions in the "spack.architecture" and "spack.concretize" modules.

* Fixed a few bugs with reading architecture information from specs.
Updated the tests to use a uniform architecture to improve reliability.
Fixed a few minor style issues.

* Adapted the compiler component of Spack to use arch specs.

* Implemented more test cases for the extended architecture spec features.
Improved error detection for multiple arch components in a spec.

* Fix for backwards compatibility with v0.8 and prior

* Changed os to unknown for compatibility specs

* Use `spack09` instead of `spackcompat` for the platform of old specs.

* Does nothing if no prexisting config.guess is found.

* Update name for RHEL OS.

Fixed a typo.

Fixed a typo.

use short spec instead of spec as CDash has a limitation in name length
mark all problems as 'FAILED' as CDash does not understand "ERRORED" status

Different compilers have different flags for PIC (position-independent
code). This patch provides a common ground to accessing it inside specs.

See discussions in #508 and #2373. This patch does not address the issue
of mixed compilers as mentioned in #508.

Package provides a 'list_url' attribute which may be searched to find
download links. #1822 created a slowdown for all tests by always
searching this URL. This reenables dynamic search only in cases where
all other fetchers fail. This also only enables dynamic search when
'mirror_only' is set to false.

Sometimes files in the stacktrace are not from spack. Remove these
files before finding the spack root.