refactor: make modules_mapping a regular rule (bazel-contrib#578)

* refactor: make modules_mapping a regular rule

* fix: remove unnecessary comment

Signed-off-by: Thulio Ferraz Assis <3149049+f0rmiga@users.noreply.github.com>

Co-authored-by: Alex Eagle <eagle@post.harvard.edu>

Release 0.5.0

Release 0.4.0

release 0.3.0

release 0.2.0

release: 0.1.0

release: 0.0.3

Add information regarding support (bazel-contrib#290)

Update README (bazel-contrib#237)

Expand the Overview. Add more context on core rules vs packaging rules and
level of support. Add instructions for using Bazel Federation. Move pip stuff
to sub-headings.