profiles/package.mask: mask leaf py2.7 pkgs

profiles/package.mask: mask leaf py2.7 pkgs

* These packages are (mostly) leaf dev-python/* packages which have no py3 impl
in the ebuild
* Packages not from dev-python/* are preceded by the relevevant dev-python/* pkg
which caused the package to be masked.
* This is just the "tip of the iceberg" of py2 only packages. As such, due to
the sheer number of packages, it is nearly impossible for any one person or
project to address them all.
* Many of these packages are likely not needed, but some will be. If you find a
package that is needed please update/port/fix the ebuild/src to support py3
* This is not a "go fix it or it dies" stance. If you can please assist in
identifying which packages have upstream supported py3 impls please feel free
to ping me to support porting the ebuild.
* There may be false positives. Sorry about that. Feel free to adjust the mask
and remove any py2 only ebuilds (e.g. multiple versions/revisions of ebuilds
and one of them only supports py2)
* Removal in 30 days

Always happy to help/assist in keeping things moving along within Gentoo.

Signed-off-by: Aaron Bauman <bman@gentoo.org>