Add new command 'check' which scans the open pull requests for another user.
Add 'xdg-open' to improve Linux support.  Always print out pull request URL in case it needs to be referenced after browser is closed.
Auto-open ticket in JIRA after submitting pull request if github.jira config is set.
Have github.reviewer be a default rather than forced each time.
Prompt for remote branch name.
Raise warning if trying to send a pull request on master.
Use environment variables instead of temporary files to return to working folder.
Do not print a warning if email names functionality is not used
Do not force reviewer
If no pull request # is specified, treat 'fetch' like 'fetch-all'
Use JIRA link as default pull request body