push/pull fixes via prepare_args
- fixed make html package inconsistency (docutils==0.15)
- moved creation of E1, E2, E2 to prepare_args, deleted evaluate_12 etc. and improved test_domain.py
- make evaluation of spline_cyl and spline_torus work (include in test_domain.py), give prepare_args ValueError, set kind="straight" default in theta, added "R0" to parameters of spline_cyl (shift pole from zero)
- adapted push/pull to new prepare_args and added tests for all possible evaluations.
- small changes is docstrings