pkgconfig is the virtual provider, pkg-config is a specific
implementation.

- Add missing pkgconfig dependency
- Explicitly disable egl

Spack can now be configured to assign permissions to the files installed by a package.

In the `packages.yaml` file under `permissions`, the attributes `read`, `write`, and `group` control the package permissions. These attributes can be set per-package, or for all packages under `all`. If permissions are set under `all` and for a specific package, the package-specific settings take precedence.  The `read` and `write` attributes take one of `user`, `group`, and `world`.

   packages:
    all:
      permissions:
        write: group
        group: spack
    my_app:
      permissions:
        read: group
        group: my_team

replace 5.1.1 with 5.1.2 as 5.1.1 does not build for me. [and 5.1.3 is preferable in this 5.1 series anyway]

* superlu-dist: Update package.py for superlu-dist v6.0.0 using CMake

* superlu_dist: Update the header of package.py

* Specify lapack_blas and DCMAKE_INSTALL_LIBDIR
disable support for superlu-dist before v5

current stable releases of PETSc and Trilinos have non-overlapping
requirements on Superlu-dist. For now turn it off by default in
Trilinos, which requires older versions.

* Better default CLI arguments for CDash reporting

--log-format=cdash is now implied if you specify the --cdash-upload-url
option to spack install.

We also now default to writing CTest XML files to cdash_report/ when using
the CDash reporter if no --log-file argument was specified.

* Improved documentation on how to use the CDash reporter

Default config.yaml mis-named `install_path_scheme` as `directory_layout`.
This commit corrects the error.

* Added VTK 8.1.1, added option to disable libharu
* Add variant description to vtk+libharu

We need to use -O3 -qstrict -qnohot. Modified ibm-xl.patch and netlib-lapack
package file.

* new xdot.py package and necessary updates to GUI libs

* new xdot.py package and necessary updates to GUI libs

* bison: Add missing build dependencies

bison also depends on cmp, which is currently not available in Spack.

* help2man: Add missing build dependency

* m4: Fix build with newer versions of glibc

* openssl: Add missing build dependency

openssl's configure script is actually a Perl script.

* texinfo: Add missing perl dependency

* diffutils: New package

* findutils: Fix build with newer versions of glibc

* mvapich2, mpich: Add missing findutils dependency

* Add option to disable threads for Geant4
* Add option to enable DagMC in MOAB
* Explicitly add OFF flag when threading is disabled
* Fix unintentional enabling of C++14 in Geant4
  The following always evaluated to True:
    'c++14' or 'c++1y' in spec:

perl scripts were pointing to /usr/bin/perl, changed to point to
the spack-installed perl

* Push default flag handlers into module scope

* Preserve backwards compatibility of builtin flag handler names

Ensure Spack continues to work for packages using the `Package.env_flags` idiom and equivalent.

* update docs and tests to match

* Update packages to match new syntax

* xerces-c: Add variant for choice of transcoder (gnuiconv, iconv, icu,
  macos, windows).  It's important to specify a --enable-transcoder
  option on the configure line or else xerces may make a different
  choice when multiple transcoders are available.
* Pass the compile flags to configure.  For cflags and cxxflags, this is
  necessary to respect the value from the spack install line.
  Otherwise, xerces (and any autotools package) will choose a default
  value that overrides the spack compiler wrapper.
* Add xerces version 3.2.2.
* icu4c needs the --enable-rpath configure option on Darwin

Includes optional extra code for compatibility with Root.

After talks with candle dev, removed unsatisfiable conflict with
candle-benchmark and opencv by disabling gtk in the candle spec