Added Zend Monitor custom event support

Change-Id: I9444cc7664911b0f925e56993239f952981f354b
Merge branch 'fix/dispatch.error' of git://github.com/YonmaN/zf2 into feature/zend-monitor-support
[#3292] CS fixes

- opening method brace
- trailing whitespace
- Removed unnecessary return statement
Merge branch 'feature/zend-monitor-support' into develop

Close #3292