ENH: Support grouping devices

[tangkong]

Expected Behavior

Support devices that are tightly coupled together, and may possibly affect multiple beam paths.

Current Behavior

Currently each device is expected to reside on a single branch, unless it is itself a branching device.

To address this problem, we simply made copies of the offending device and dropped it into each beam path. This made the device visible in all the paths, but the duplicate devices could cause confusion down the line

Possible Solution

Group devices together, and implement veto logic?

Context

Inspired by this ticket, and the case where mec_yag0 was close enough to mr1l4 to block beam for all FEH hutches.

Your Environment

pcds-5.6.0