Add PTZ control files and camera presets for specific ptz cameras.

Add camera control files and presets for these cameras:
Foscam FI8620
Foscam FI8608W
Foscam FI9821W
Loftek Sentinel PTZ

Adds just a preset for this camera:
Airlink 777W PTZ (uses existing skyip ptz control)

NOTE: I mistakenly created my first commit w/o first deleting those ~ files that gedit likes to leave hanging around.  The second commit deletes those nuisance files.