BF: in _repr_attrs do not print repr of methods. Close #122

It is a rare case but we do not have any other machinery to prevent
going into infinite recursion for those cases where bound methods
also given as parameters (callable)s.  Thus now it would only print
class where this method was bound.  If it is necessary to discover
the actual instance -- enable ID_IN_REPR debug variable
Merge branch 'master' of https://github.com/PyMVPA/PyMVPA
BF: RSA measures changed to return column vector datasets. This was necessary to have searchlight results make sense.