issue-branch reordering

Starting #5
Extract git._run_command method
Move git logit to git module
Code is PEP8 compliant
-l/--list argument for listing issues
Parsing repository name and user from url when possible
Implement issue list for github
Sorting issues
Implement issue list for bitbucket
Use GH and BB APIs to obtain issue titles instead of parsing HTML
--noop option and help messages
Merge branch 'issue-5-support-for-listing-issues-issue-branch'

Closes #5