Repo Label Standardization

[spring4175]

#1432 inspired me to take a look at our labels and standardize them. Here's what I've done:

• Rename t-github-actions to t-ci
• Rename t-feature to t-feat
• Rename t-release to m-release; like m-breaking-change in that it is related to the project but does not have final inherent meaning or purpose
• Deprecated t-enhancement; this label should not be used anymore. Previous instances should be relabeled as t-refactor, t-perf, t-feat, or other appropriate labels so we can remove it. It's now named t-enhancement-DEPRECATED with a scary red background
• Introduce t-perf for PRs with the intent of improving performance
• Introduce t-test for PRs with the sole intent of adding or refactoring tests

Now that we don't have t-enhancement anymore it will be easier for us to determine whether something is a new feature, thus requiring a new minor version.

Labels are now based on conventional commit types, and more specifically the Angular convention. Therefore, commits should also follow this standard.

[7596ff]

There are a few things that I would like cleared up in our spec:

• t-test label states that it should only be applied to issues and PRs that ONLY deal with tests, but this announcement says that it can be combined with t-refactor.
• I like the idea of conforming to an existing specification, so we should rename t-feature to t-feat.

[spring4175]

I have also deprecated t-chore.