Rewrite lexer

[maanlamp]

The lexer works but I cannot remember what anything does. That's bad. Please rewrite your horrible mess you dummy.

[maanlamp]

Keep in mind issue #4 when doing this!

[maanlamp]

Done.

Rewrote large blocks of unintelligible expressions and statements into functions with proper names.
Also as per #4 , I've learnt how to use streams and utilised them for this rewrite.

See the modified Lexer.js in maanlamp@801c438e65cf0d0eab0f8d028d7e045e286a32fe.

There's a problem now though, when a grammar has limitless quantifiers, it will register false negative matches, resulting in errors in places where it should not error.

this.limitlessQuantifiers = /[*+]|.\{\d,\}/;

I truly am not experienced enough in using streams to know a solution to this. I'm leaving the issue open and attaching new labels.

[maanlamp]

Lexer is now v1.0 5a74377

No streams are implemented in the official release because of severly faulty lexeme recognition errors.
Lexer will be decoupled into a separate repository later on.