Removing the 'documenting' capture assignment fixes #19

Some grammers define capture assignments with as sole purpose to document the regular expression. This causes the embedded assignment of the entity.name.function scope to the last letter of a class method name.

After fixing the grammar, the tokens look like this for the same example:
![tokens after fix](https://cloud.githubusercontent.com/assets/151054/3806230/2adbd38c-1c47-11e4-94e5-7620df8f7a8c.png)