Bumped pom to 2.4.0-SNAPSHOT
Notify jenkins on a separate thread to release Stash's event thread

In the worst cases Jenkins has been known to block, resulting in Stash
running out of event threads, which is Bad.
Merge branch 'notify-background-thread' of github.com:charleso/stash-jenkins-postreceive-webhook into charleso-notify-background-thread
Make plugin backwards compatible with Stash version lower than 2.8
* Fix js error on pull request page
* Bind trigger button on document.ready
Bumped version to 2.3.1
Added release notes to README
Merge branch 'develop' into v-2.3.1

Conflicts:
	pom.xml
Removed SNAPSHOT from version and updated README
Merge pull request #57 from Nerdwin15/develop

Develop