Taken from PR 199780 with minor modifications.
Proposed commit message:
new port: security/omniauth-bitbucket Ruby gem to add an OmniAuth strategy for Atlassian Bitbucket. WWW: https://github.com/sishen/omniauth-bitbucket PR: 199780 Submitted by: Torsten Zuehlsdorff <ports@toco-domains.de> Approved by: swills (mentor), mat (mentor)