Fix lumix camlib compilation warnings.
Fix lumix camlib compilation warnings.

Resolves couple signed-unsigned comparison issues, fixes one uninitialized 'nRead' variable read bug and comments out or removes number of unused functions and variables.

gphoto/libgphoto2,gphoto/libgphoto2,gphoto/libgphoto2,gphoto/libgphoto2,gphoto/libgphoto2,gphoto/libgphoto2