API 2.0

[kahaaga]

This is the cleaned-up version of #97 (which I am keeping temporarily, to have access to timings). When tests pass and documentation looks ok, we can merge this and delete #97.

[kahaaga]

All the examples in the documentation seem to do what I'd expect them to do, so this is good to merge from my side.

That is actually not true. The LombScargle example looks off. I'll have a look over the weekend.

[Datseris]

Just tag me when you want a final review here!

[kahaaga]

@Datseris I've removed redundant comments and tried to style the code in a more paragraph-like style. Not all comments were removed, because I still think they're useful, but comments are not in place during every step anymore.

I also think the IrregularLombScargle example works fine now. The mistake was that I set the default number of maximum iterations too low, so that the Lomb-Scargle periodogram of the surrogate wouldn't converge sufficiently to the periodogram of the original surrogate. This is now fixed.

Should be ready for another review.

[Datseris]

@kahaaga wow, now that's one huge amount of work, congrats! I think I went through all of the PR. I've left only really small comments that you can easily address. Feel free to merge after you have addressed the comments!