Added /v2/claim API endpoint with tests.

This should fix #121, though I'm not sure where to document the endpoint...
split out api badge-awarding tests into a separate suite.
Merge pull request #136 from toolness/issue-121-api-claim

Issue 121 /v2/claim endpoint
added notes on the different branches, etc.
added .travis.yml.
added travis badge
removed webmaker copy from csol theme. it was buggin me out.
throw a more helpful error when mongodb env vars not present.