UserDefinedSerial: Avoid VC++ warning

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@14365 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd
UserDefinedSerial: Add UserDefinedGenericDevice

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@14366 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd