Use `BEAMLINE_ACRONYM` as default

[danielballan]

We now define BEAMLINE_ACRONYM in the workstation environment via profile.d.

The sync_experiment module should be updated to use that as a default value, if set. https://github.com/NSLS-II/nslsii/blob/master/nslsii/sync_experiment/sync_experiment.py

Also, in the directory there is a stray .DS_Store file, accidentally committed, that should be cleaned up.