Ticket 3465-1: Slide limits

[John-Holt-Tessella]

As an instrument scientists I want the slide axis to be limited in its motion.

Acceptance Criteria

• Limited motion is defined (current code looks wrong and is hard to implement)
• Motion is limited as defined

Notes

POLREF instrument scientists will confirm what the motion limit is
Continuation of #3465

[John-Holt-Tessella]

Slide motion is limited by bench angle. Bench angle is limited to <=0 and >=4.8.

[John-Holt-Tessella]

pull requested

• Limit slide position based on angle EPICS-refl#11