Register events via the boot method

This ensures that we only register 3 events per class as opposed to registering an 3 events for every instance of the class.
Allow use of Laravel 4.x
Merge pull request #19 from rtablada/master

Allow use of Laravel 4.x instead of just 4.0
Merge branch 'master' of github.com:CodeSleeve/stapler into development
version bump
Merge branch 'master' of github.com:mohangk/stapler into mohangk-master

Conflicts:
	composer.json
Merge branch 'master' of github.com:CodeSleeve/stapler into development