PICAM: Avoid returning invalid device name

(When GetName() called before Initialize().)

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@14696 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd
PICAM: Remove some dead code

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@14697 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd
PICAM: Fix crash on setting certain properties

In practice, the crash was observed with the "Port" (readout port) property.
The cause was a confusion between PICAM enum values and the index of enum
values, leading to an out-of-bound array index.

There appears to be a separate issue that prevents correct setting of the
"Port" property, which is not addressed in this commit.

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@14698 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd