IdIterator fix TypeError: _call() got multiple values for keyword argument 'max_id'.

The problem is that max_id is passed in self.method as param but also
kept in kargs. Doing a kargs.pop with None as default value for 'max_id'
solves the problem as not keeping 'max_id' in two places anymore.
Merge pull request #446 from andreip/master

IdIterator fix TypeError: _call() got multiple values for keyword argumet 'max_id'