v1.23.3

-- The changes to implement distributed storage in Homer3 removed up front error checking because when it's configured acquisition data isn't loaded right away, so it isn't error checked. This implements a graceful loading even is acquisition files are not valid and pushes the rror checking to a little later in the Homer3 startup process. It add to the Load methods an err return value signifying if loading was successful and if the loaded file was valid or invalid. When clicking on listbox entries it doesn't allow display unless the SnirfClass loader returns without error.

-- Fix small bug where Settings menu callback (which isn't needed) was deleted in MainGUI.m but was NOT in MainGUI.fig