Gaussian plugin: fix isuue in ParticlePairLister

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@14835 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd
MMCore: Unload all devices after cfg loading fails

This prevents uninitialized devices from being left over. Such devices often
cause a crash when thier methods are called, including when the user next
attempts to load a config file.

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@14836 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd