Add semantic versioning tagging



Deploy Plan
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Does Infrastructure need to know anything special about this deploy? If so, keep this section and fill it in. **Otherwise, delete it.**

Rollback Plan
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**If this pull request requires anything more complex (e.g., rolling back a migration), you MUST update this section. Otherwise, delete this note.**

To roll back this change, revert the merge with `git revert -m 1 MERGE_SHA` and perform another deploy.

URLs
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* [Jira issue MOBILE-635](https://sportngin.atlassian.net/browse/MOBILE-635)

QA Plan
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Provide a detailed QA plan, or other developers will retain the right to mock you mercilessly.

Keep in mind that this is an open source gem, so others outside of our organization might want to make use of it as well.  Not sure if we want to support the `pre` and `build` attributes for the version, but I think having a regex that is already tested and used elsewhere is a benefit to us, and also helps make sure that the tag string that gets passed into `semantic` works correctly.