ENH: extend iocmanager, imgr wrappers to allow for R3.0.0

[ZLLentz]

Description

The wrapper scripts for iocmanager and imgr have been modified to allow for either the "old" (py2, rhel7) or the "new" (py3, rhel7/rhel9) versions of iocmanager during this transition period.

The intention is to deploy this during the shutdown.

Motivation and Context

This allows people to use the new iocmanager (R3.0.0+) when they are ready.

How Has This Been Tested?

Interactively only
Probably it needs more testing

Where Has This Been Documented?

Here only

[ZLLentz]

Marking this as ready for review with the intent of merging next week concurrent with the release of iocmanager R3.0.0

[ZLLentz]

I'd appreciate being able to merge this this week so we can try R3.0.0 of iocmanager as the main iocmanager for the tst subnet (and maybe for txi?) @pcdshub/engtools-team

[KaushikMalapati]

On line 70 in imgr and line 46 in iocmanager, there are old checks for unknown_hutch that I think should be removed because they are not possible to enter anymore

[ZLLentz]

Thank you Kaushik, I'll fix these tomorrow morning. I should have been more careful here.

[KaushikMalapati]

Thank you Kaushik, I'll fix these tomorrow morning. I should have been more careful here.

I think the only problem was the hutch path - this probably worked when you tested it, but it would have always returned false on the check for scripts/gui.sh since the base directory didn't expect and fall through to the R2 handling, which happens to currently be correct since no hutch is using R3.0.0+.

[ZLLentz]

I think I've resolved all the issues above

[ZLLentz]

ok, I think I want to release iocmanager in its current state before lunch so I can move on with my life (and use it for the TXI migration). Even if there are no approvals I'm going to merge this in the next 15-20 minutes or so.