Gaussian plugin: further refactoring of DataCollectionForm

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@14820 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd
Gaussian plugin: Factored out pair listing functions from DataCollectionForm

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@14821 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd