Re-Re-Structure some Overlays

[baconpaul]

The overlay mechanism is fine but there's some restructuring I would like to do to it

1. Lets move the overlay functions to SurgeGUIEditorOverlays.cpp - SGE getting too big
2. Rewrite the patch save dialog in juce. That would let us use juce::ComboBox for category also which brings Add menu list of all existing preset folders to Patch Store #1840 back from the dead (I think a save dialog outside the patch browser still makes perfect sense)
3. Rework the open/close functions to be a bit more data driven. I worry that we don't actually need quite as much if-stuff in the open and recreate for instance. This will tie in tightly with the fix to XT Crash with overlay and FX select #4541 so lets do them simultaneously