Handlebars Compiler

Addition of a compiler for handlebars templates.

Defaults to in place, and version 1.3.0.
Do you still need this even after the refactoring? You can correlated with a full example here, for liveScript: https://github.com/madskristensen/WebEssentials2013/pull/1009/files. Similarly, SweetJS was added at once: https://github.com/madskristensen/WebEssentials2013/pull/683. 

The exception is, you don't have preview window, for which you can relate to CSON support: https://github.com/madskristensen/WebEssentials2013/pull/1470.