Updated CoffeeScript to 1.6.2 in worker-coffee

As per [google groups thread](https://groups.google.com/forum/?fromgroups=#!topic/ace-discuss/5qOeABNJXZs)

Note that I only fixed the yylineno, but I haven't tweaked the parsing of error messages (seems to work fine on first glance and there doesn't seem to be a full test suite for all errors in CoffeeScript).
```
also format of other errors have changed, so
https://github.com/ajaxorg/ace/blob/master/lib/ace/mode/coffee_worker.js#L56
needs to be tweaked 
```
(Let me know if it's ok to merge and I'll go through the hassle of signing the license).