ConfigDialog: Fix bug reported by Jon Daniels, and clean up code a bit

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@14707 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd
[TIFF saving] Fix a bug that breaks split-by-stage-position saving.

In particular, if any image is generated with no "PositionName" tag when the
"Save XY positions in separate files" option is set, then that image will be
saved to the file for stage position 0. This can create multiple
MultipageTiffWriters for the same file, which can trample each other and
corrupt file data.

Fortunately, currently this never happens in normal operation, because separate
code ensures that the PositionName tag is always created. Still, bad practice.

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@14708 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd
Plugin Makefile: Escape pwd call so that it also works on paths with spaces

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@14709 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd
PICAM: Prevent failure to set EM gain

This prevents the EM gain property from reverting to the original value when
attempting to set it while an acquisition is _not_ running. It is a partial
fix, in that setting the property while running Live in MMStudio does not yet
work, and it has not been confirmed whether the set value is correctly
reflected in the next acquisition.

Change contributed by Toshio Suzuki.

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@14710 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd
Mightex_C_Cam: added dll files

git-svn-id: https://valelab.ucsf.edu/svn/micromanager2/trunk@14711 d0ab736e-dc22-4aeb-8dc9-08def0aa14fd