Yelp gym updates

[tvaroglu]

• Changes Implemented:

  • Added encrypted yelp_api_key to .travis.yml, and un-gitignored cassettes to get Travis builds to pass. API key has been added to Heroku, so we won't have failing API calls after this PR is merged in
  • Created migration to add name to Gym table, factories, and as additional attribute to serializer, so the endpoint will render this for user dashboard view (currently only displaying yelp_gym_id)
  • Added helper method to User model for upcoming_events. The users/:id/events endpoint now renders events from this method call (vs just .events prior)
  • Will be updating /docs as final step of this PR for refreshed endpoint examples based on DB-reseeding (PK's have changed the static URIs linked within ReadMe and docs)

• Quality Control Checklist:

  • [x] Code adheres to Rubocop styling (if unavoidable infractions, please clarify below)
  • We have some infractions across the state of the repo, but most are due to pending examples, or longer method calls that we have already clarified comments to slim-up as todo items.
  • Suspecting that we will comb back through all of these during a later stage of the project
  • [x] 100% SimpleCov test coverage (if below, please clarify below)

• Blockers (if applicable):

• Next Steps & Additional Notes:

  • Need to reseed DB for FE team and update docs for endpoint examples