Fixed unbound methods getting their first parameter curried
Fixed test compatibility wrt/ unbound methods on py3.0+
avoid superfluous use of itertools.chain
Merge pull request #3 from epsy/unbound

Fixed unbound methods getting their first parameter curried

Ensures the the 'self' argument of methods on un-instantiated classes appear in the function signature on both Python2 and Python3. Also ensures self is identified correctly as a positional-only parameter.