Gherkin support

Hacked into shape from this
https://github.com/cucumber/gherkin-syntax-highlighters
Ignore RubyMine cruft
Capture do, end, /^step def text$/
Gherkin test (I think)
Gherkin done
Step Defs

I think this is a bit simplistic, but it works
Added Monkey language support
Fixed header detection of function and method
Improved relevance for Monkey language
Improved variable type detection for Monkey language
Merge branch 'monkey-language' of github.com:devolonter/highlight.js into monkey
Resetting most custom relevances in monkey.js.
Resetting even more custom relevances in monkey.js keywords.
Gherkin definition
Merge branch 'feature-gherkin' of github.com:matteofigus/highlight.js into gherkin

Conflicts:
	.gitignore
Tuning Gherkin relevance:

- reset custom relevances in Gherkin
- zeroed relevance of the common phrasal word "the" in AppleScript
Moved Gherkin snippet to the end of tests, removed step_definitions snippet.
merge + step_definition removed from tests
Relevance fixes for #436:

- reset relevance of %-comments in Erlang
- added relevance booster for dots at the end of line in Erlang
- reset high relevance for %-strings in Ruby (it's rare anyway)
- specialized the simple `{..}` variant of MatLab cells to have zero relevance
css classes reference added