Update SQL Database with info from PVs.

[eloise-nebula]

A lot of our configuration comes from Oracle/AIDAList, but some of it is changed during operation through PVs. It would be convenient to save that configuration information live. For cases like this:

slicops/slicops/device/__init__.py

Lines 262 to 266 in dc9677c

	if self.accessor_name == "image":
	# TODO(robnagler) this has to be done here, because you can't get pvs
	# from within a monitor callback.
	# TODO(robnagler) need a better way of dealing with this
	self._image_shape = (self.device.get("n_row"), self.device.get("n_col"))

Would possibly have to watch for changes in these maintained PVs for responsiveness.