Cpymad

- close handles in remote process properly on all supported python versions
- rewrite ``libmadx.get_table`` functionality
- madx functions that return tables now return proxy objects instead. For
backward compatibility these can be iterated to allow unpacking into a tuple
- the returned table columns is now a proxy object as well and not ``TfsTable``
- remove ``retdict`` parameter
- move some cpymad specific functionality into the cpymad package
- add libmadx/madx functions to access list of elements in a sequence

- add ``AttrDict.update()`` method similar to regular dicts
- add ``Table.row_names()`` query method
- use row names as table index for pandas dataframe
- add ``Madx.batch()`` context manager to collect commands before sending them
to MAD-X in a single batch all at once (performance)
- add a convenience parameter ``Madx(history=[])`` to simplify capturing
history
- explicitly specify ``zip_safe=False`` for the cpymad package. This will work
better for builds against shared MAD-X library
- close CommandLog files when calling ``Madx.quit()`` (if they were opened
by us)

Finally, this is the first release to automate the release process for windows
wheels:

- build windows wheels on appveyor
- upload windows wheels to pypi on tags
- test cpymad on windows using appveyor

- update official support to ``MAD-X 5.02.13``
- cache columns in TableProxy
- add fast functions to obtain element positions

- in setup: disable unsupported ``--no-as-needed`` on Mac
- in setup: allow value of ``--madxdir`` to be specified as separate argument
- format ``types.Expression`` in commands
- fix formatting of ``types.Constraint``

- Build windows wheels against the real (July) 5.04.01 release of MAD-X

- serve globals as ``Parameter`` instances from libmadx module
- add ``cmdpar`` attribute to ``globals``