Several driver bugfixes and small improvements

[thangleiter]

This PR makes several bugfixes and small improvements.

Attocube ANC350

• Adds a setter for the Attocube ANC350 position parameter.

Horiba FHR

• Adds an active_grating parameter.
• Use built-in offset argument for the width parameter of slits.
• Make port openess a parameter.
• Give channels a label.
• Wrap requests to the dll a qcodes.utils.DelayedKeyboardInterrupt context.

Aviosys IP Power 9258S

• Update the instrument class name to follow convention and deprecate the old class.
• Remove the set parser for power_enabled.

Lighthouse Photonics Sprout G

• Make enabled a DelegateParameter of output_status.

Msquared Solstis 3

• Improve wavelength lock acquisition logic.
• Add table wavelength tuning.
• Improve snapshot behavior

Thermotek T255p

• Drop watchdog timeout. Contrary to the manual I have, it does not appear to be necessary.
• Do not get parameters on snapshots (takes a long).