Ci is currently failing on brew update with the error:
```
Error: Cannot install bazelisk because conflicting formulae are installed.
  bazel: because Bazelisk replaces the bazel binary

Please `brew unlink bazel` before continuing.

Unlinking removes a formula's symlinks from /usr/local. You can
link the formula again after the install finishes. You can --force this
install, but the build may fail or cause obscure side effects in the
resulting software.
```
Avoiding:
```
$ brew update
$ brew upgrade
```
solves the issue by preventing the risk of conflicting formulae

With experimental CUDA support and some patches to make it compile.

Currently +shared and +cuda conflict, this has to be fixed upstream.

* Run Python2.6 unit tests on Github Actions
* Skip url tests on Python 2.6 to reduce waiting times
* Skip foreground background tests on Python 2.6 to reduce waiting times
* Removed references to Travis in the documentation
* Deleted install_patchelf.sh (can be installed from repo on CentOS 6)

* Update LBANN, Hydrogen, Aluminum to inherit CudaPackage
* Update CMake constraints: LBANN, Hydrogen, and Aluminum now require
  cmake@3.16.0: (better support for pthreads with nvcc)
* Aluminum: add variants for host-enabled MPI and RMA features in a
  MPI-GPU RDMA-enabled library
* NCCL: add versions 2.7.5-1, 2.7.6-1, and 2.7.8-1
* Hydrogen: add version 1.4.0
* LBANN: add versions 0.99 and 0.100
* Aluminum: add versions 0.4.0 and 0.5.0

* new package(s): py-gql

and related dependencies:
py-aiohttp
py-async-timeout
py-graphql-core
py-idna-ssl
py-multidict
py-websockets
py-yarl

new versions:
py-requests

* fixes

Co-authored-by: Andrew W Elble <aweits@skl-a-00.rc.rit.edu>

* Add versions 2.2.1 and 2.2.0
* Remove version 2.1.0
* Add dependency on Java

* py-mixedhtseq: new package at 0.1.0

* py-mixedhtseq: flake8 fixes

* py-gpy: add 0.8.8

* py-gpy: remove unneeded dep

* py-gpy: make cython build-only

* NWChem 7.0.0

* add python2 for 6.8.1. removed 6.8 https://github.com/spack/spack/pull/17779#discussion_r462700413

* nwchem 6.8.1 breaks with gcc 10 and later

* restored extra python bits for version 6.8.1. add env. definition of basis libraries

* changes for flake8

* url fixed

* prevent 6.8.1 being compiled with gcc 10

* new package(s): py-torch-geometric
(with related dependencies: py-rdflib, py-googledrivedownloader)

* fixes

* Ferret: Add missing dependency with curl.

* Ferret: Don't force using the static version of libgfortran.

* Ferret: Ensure Spack's compiler wrappers are used.

This allows properly setting the rpaths.

* Ferret: Add support for versions 7.3 to 7.6.

* Ferret: Add a variant to install Ferret standard datasets.

* Ferret: Define some useful runtime environnement variables.

* Ferret: Fix flake8.

Also add myself as a maintainer as suggested by @alalazo.

As discussed in issue #17638, wherein kahip fails to build when
scons is dependent on python@3.

This converts the print statements in various SConstruct files
into python3 friendly print functions.

I found most of the affected SConstruct files in both @2.00 and
the later versions I found on web, but some files were only in @2.00.
I split the patches into two files for that reason, but have not
tried the later versions.

* [dd4hep] add new patch version

* [podio] add new version and update env vars

* [dd4hep] add hepmc3 variant

* LAMMPS: Use LATTE 1.2.2 starting with version 20200602.

Version 20200602 and upper requires Latte 1.2.2. This caused the internal Latte distribution to be used instead of the Latte install provided by Spack.

* LAMMPS: Add new versions 20200630 and 20200721.

* dcmtk: fixed type error

* Update var/spack/repos/builtin/packages/dcmtk/package.py

Co-authored-by: Adam J. Stewart <ajstewart426@gmail.com>

Co-authored-by: Adam J. Stewart <ajstewart426@gmail.com>

* New package: IDL

* Update var/spack/repos/builtin/packages/idl/package.py

Co-authored-by: Adam J. Stewart <ajstewart426@gmail.com>

* Update var/spack/repos/builtin/packages/idl/package.py

Co-authored-by: Adam J. Stewart <ajstewart426@gmail.com>

* added license header and changed url_for_version to just url

* removed unused imports, addressed comments

* removed trailing whitespace on line 14

Co-authored-by: Adam J. Stewart <ajstewart426@gmail.com>

* mozjs@1.8.5: fix compile issue

* mozjs: refine method

Co-authored-by: Daryl W. Grunau <dwg@lanl.gov>

* py-uvw: added package for versions 0.0.7 and 0.3.1

* py-uvw: added py-setuptools as dependency

Also added older version in the 3.6 and 3.5 series