- simplify output, error, and input redirection
- `return_output=True` is now `output=str`
- `return_output=True` will still work for the time being but is
deprecated.
- previously you could say `return_output=True` and `output=<stream>`,
which wouldn't actually write to the stream. Now you actually can't
specify erroneous cases since there is only one parameter with
mutually exclusive options..
- This moves var/spack/packages to var/spack/repos/builtin/packages.
- Packages that did not exist in the source branch, or were changed in
develop, were moved into var/spack/repos/builtin/packages as part of
the integration.
Conflicts:
lib/spack/spack/test/unit_install.py
var/spack/repos/builtin/packages/clang/package.py
Package repositories now look like this:
top-level-dir/
repo.yaml
packages/
libelf/
package.py
mpich/
package.py
...
This leaves room at the top level for additional metadata, source,
per-repo configs, indexes, etc., and it makes it easy to see that
something is a spack repo (just look for repo.yaml and packages).
