Allow nogil for most types of methods

[jpfeuffer]

This requires a change in conversion providers.
+Some other cleanups.

[jpfeuffer]

I will fix tests because of newer typing syntax

[poshul]

This looks good to me. Any idea what sort of performance improvements we are likely to see?

[jpfeuffer]

Probably none out of the box.
But it allows to use our functions in a multi threaded python context e.g. via the python threading module.

This brings some responsibilities for the user with it but you can decide which functions are safe to use.

[timosachsenberg]

Not super confident that I understand all parts. Would be great if in general methods would contain a brief comment e.g.the new _split one etc.

[jpfeuffer]

This is a breaking change. Be prepared to fix OpenMS if you merge this.

[poshul]

Given that we already need to do some fixes for OpenMS to get it to work with the current develop version of autowrap, I'm good merging this in and planning to have the core group sit down and fix at some point in the future.

[timosachsenberg]

what needs to be done to work with the current develop version of autowrap otherwise?

[timosachsenberg]

and what would need to be fixed?

[poshul]

and what would need to be fixed?

#186