Cpymad

- fix order of ``weight`` command in ``Madx.match``

- expose directory of global MAD-X variables as ``Madx.globals``
- expose directory of global MAD-X elements as ``Madx.elements``
- fix a bug with Elements.__contains__ reporting yes incorrectly
- list only those column of a table that are marked for output
- add function to get row names of a table

- fix deadlock if accessing the global ``cpymad.madx.metadata`` object with
closed or invalid STDIN (after ``os.close(0)`` or in windows GUI application)

- add some utility functions to work with MAD-X element names and identifiers
- add a setter method for values to Madx
- improve install instructions. In particular, recommend WinPython as build
environment
- fix the MinGW build error due to broken sysconfig inline
- run setup only if invoked as main script

- update to MAD-X 5.06.01
- halfen linux wheels sizes by building with -fvisibility=hidden and -flto,
hopefully increasing performance
- internal improvements with the CI setup:
- CI tests more configurations than before
- CI tests should now run on pull-requests
- reduce complexity