pybond: need a better way to exclude 'self'/'cls'

[xkrogen]

Current way that we exclude the self and cls parameters is hacky. Need something better

[gnecula]

I'd say that we exclude the 'cls' always. I have written some code to try to detect what kind of function we are annotating, but unfortunately it is not very solid.

As for spying 'self' I can imagine that sometimes we want that. But this is related to how we serialize instances (relates to issue #5)