Minor bug fix with which messages we listen for hubot to respond to

Hubot will now respond to "hubot pr" and not things like "hubot what's on prod?". Thanks @davedash!

Adding support for GitHub Enterprise Users

Check out the README! You can now configure which URL we communicate with GitHub's API (hint hint - a GHE instance).

PR Assignee will now send out (if present!). Also, Slack messaging should have prettier output!

From Dave Dash (@davedash):
#3
#4

Added a CHANGELOG.md.

Adding support for using a GitHub User instead of a GitHub Team

You can now set an environment variable, GITHUB_PRS_USER, instead of GITHUB_PRS_TEAM_ID to list all pull requests on repos that the user owns. Note: GITHUB_PRS_TEAM_ID will take precedence over GITHUB_PRS_USER.

Initial Release

1.0.1

Update README.md