Move template handling into spotter core

Start separating GUI and template handling.
Add list of recently used templates to menu

Including renaming of some remnants of calling templates "configs".
Save AlwaysOnTop main window state
M: Formatting
Move template handling to tracker adding methods

Moved handling of template specifics to the adding functions of tracker.
There is no link the the Qt GUI yet, so tabs are not created for new
features, OOIs and ROIs. Adding new those other than via loading of
templates is non-functional, too.

Also further renaming of "led" to "feature" to reflect future
generalization of things to track.
M: More led -> feature renaming along the way
Tracker basic template handling restored

Most of the template handling is working again. Component tab pages
can't create new components yet due to default template handling.
M: Reduce margins around video frame

Those huge margins are annoying. First step is to remove margins/spacing
by layout.
M: Don't immediately start playing video on load
Tabs can add components using default template
M: Fix playback speed control work-around
Sunken panel look for video frame