New improved Fast Parser

Well, actually it's still tediously slow and bug prone.

But basically the goal is to have a more stable and especially faster parser.

The basic idea is splitting your code into functions/classes. The parts only need to be parsed when they change.

This is my last big milestone to the next release. This feature was always the reason why we didn't release (the old one was bug prone AND slow sometimes).

The following issues are still remaining:
- [x] implementation
- [x] speed
- [x] memory issues (750 mb test suite)
- [ ] stability testing
- [x] removal of some last bugs

And seriously: It doesn't look like much. But I've had tons of headaches because of this issue. For half a year! I wanted a proper, short implementation while still remaining independent of `parsing.py`. That's easily possible. But everything needs to be fast. It's not fast yet, but at least it's fast in my head, so I have high hopes.

~ David