Log the name of the file that fails to compile from cs2js
Say which file required a module that doesnt exist

Conflicts:
	src/emport.coffee
Pass compilation errors up the callback chain

When a file fails to compile it should hand the error up the chain.
Decorate the error with the name of the file that failed to compile
Merge pull request #9 from mcculloughsean/throw-error-with-filename

Throw more useful errors