Proof-of-concept automatic MEDM ADL converter and loader

[klauer]

Considered a proof-of-concept because 1 prerequisites are is not yet merged.

Prerequisites

#578 (merged here for convenience, or rather out of necessity for the converter to work)
My branch of adl2pydm https://github.com/klauer/adl2pydm/tree/ref_in_memory (tweak to allow in-memory conversion of ADL screens)

Functionality

Actual functionality only in 2 small commits: bf560cb, 753e8f7

Result

$ pydm ~/Repos/adl2pydm/tests/medm/mca-R7-7-mca.adl
[2021-03-18 17:00:10,549] [ERROR   ] - Loading /Users/klauer/Repos/adl2pydm/tests/medm/mca-R7-7-mca.adl file by way of load_adl_file...
[2021-03-18 17:00:10,607] [INFO    ] - Environment variable PYDM_DISPLAYS_PATH is not defined.
[2021-03-18 17:00:10,607] [INFO    ] - file not found: stylesheet.qss
[2021-03-18 17:00:10,607] [INFO    ] - writing screen file: None

Screenshot

Why?

• We want areaDetector screens and other community-provided ones easily available at some point.
• areaDetector provides ADL screens in its standard distribution as do many other packages.
• Ideally, EDL (EDM) loading would be added at some point with a similar hook. This is really what PCDS would like in the end.

[hhslepicka]

That looks really cool! Thank you for the PR and generalization of the load file... that opens up some nice possibilities.
I will work on getting the PyDM widgets PRs reviewed and merged so we can move this forward.
For now I left 2 small suggestions.

[klauer]

Thanks, @hhslepicka. 👍

(cc @prjemian for input as this is based on his project)

[hhslepicka]

#578 was merged in...
Once BCDA-APS/adl2pydm#59 is in let's rebase and get this change in...

[klauer]

Rebased and tested briefly:
pydm -m P=sim:,M=mtr1 ~/Repos/adl2pydm/tests/medm/motorx_all-R6-10-1.adl

Looking pretty good overall:

[hhslepicka]

Thank you for the great addition @klauer! This will open a very nice path towards more converters...