[CLEANUP] Get rid of Liquid.log
[TEST] Added tests for some block behaviour
[COVERAGE] Improved some code where CoffeeScript would reduce coverage
[FIX] Fixed an exception hiding the real sytax-error that caused it
[TEST] Added some tests for `contains` operator
[TEST] Added a test for empty variables
[TOOLS] Change renderTest to accept RegExp for `expected`
[FIXED] Fixed handling of FilterNotFound errors