move existing tests to rspec
create unique login token for each user
Add more examples of how to embed the badge in different file formats.
Adds bitbucket support

This adds backend support for bitbucket repositories.
Missing:
- An interface to add bitbucket projects
- Remove some hardcoded github links (mostly views)

Limitations:
- Bitbucket API only allows fetching 15 commits at a time.
Uses reversible dir.up in migration
Merge pull request #53 from hugopeixoto/bitbucket-support

Adds bitbucket support
Merge pull request #46 from kuldeepaggarwal/modify-existing-test-cases

move existing tests to rspec
Merge pull request #47 from kuldeepaggarwal/fix-set_login_token

create unique login token for each user
Merge pull request #52 from mikebryant/feature-embedding-urls

Add more examples of how to embed the badge in different file formats.