Bazel Updates for math6

[mjcarroll]

Rebase the bazel branch to be off of math6, the version used in dome.

Specific cleanups and feedback incorporated in 18b35a0

This will replace the current bazel branch.

[codecov]

Codecov Report

Merging #171 (90cbf4b) into ign-math6 (1e9ce65) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           ign-math6     #171   +/-   ##
==========================================
  Coverage      99.20%   99.20%           
==========================================
  Files             63       63           
  Lines           6019     6019           
==========================================
  Hits            5971     5971           
  Misses            48       48           

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[JShep1]

Builds and runs fine with all tests passing for bazel and colcon

[scpeters]

are we going to setup CI for bazel to prevent regressions?

[JShep1]

Just added the Capsule class. This brings up a good point, perhaps we eventually want to glob for files? We're globbing for tests so it will automatically break CI if someone adds new files and tests for them since the bazel build files will pick up the new tests but not the new files.

[chapulina]

I don't know much about Bazel, but I didn't notice anything weird, and CI that's using this branch seems to be happy with ign-math:

https://github.com/ignitionrobotics/ign-bazel/runs/2068842483?check_suite_focus=true

The branch for that build is configured here:

https://github.com/ignitionrobotics/ign-bazel/blob/6c7128cb4833bbbb06d397f785c61d02d7f8b962/.github/ci/bazel.repos#L5