Removed my .jshintrc file.

It was only defining some globals and meant that everyone elses
~/.jshintrc files were ignored.
Corrected the name of a test suite.

setOnceReturnValuea -> setOnceReturnValue (remove the a on the end)
Added a test case for once within once listeners.

Trying to cause issue #51
Removed the qwery include from the test file.

It wasn't actually used for anything and caused a 404.
Cleaned up the tests linting.

assert is no longer defined globally and JSHint has nothing to complain
about.
Just added a space after the test wrapper function

Just being picky.
Converted all counting tests to be stronger.

Now I am checking for what listeners were executed / removed etc, not
just the amount of listeners executed. I was hoping this would flag up
some issues I could fix, looks like I wrote this better that I
originally thought.

Everything seems fine even after checking a lot more. What a nice
surprise.

This is part of #51
simplify removing listener.listener
Bumped the version number to v4.2.1.
Built v4.2.1.
Merge branch 'develop'