libs: loaders: GP_Loader.c: Cleanup.

Get finally rid of the big piece of old code.

Signed-off-by: Cyril Hrubis <metan@ucw.cz>
doc: loaders, environment_variables: Update.

Signed-off-by: Cyril Hrubis <metan@ucw.cz>
input: Add timers and timer priority queues.

Signed-off-by: Cyril Hrubis <metan@ucw.cz>
input: Add GP_GetTimeStamp() function.

The function returns number of miliseconds from some point
(boot of the machine, start of the program, 1. 1. 1970 or anything else).

Signed-off-by: Cyril Hrubis <metan@ucw.cz>
backends: Add support for timers to backends.

Now you can add any number of timers to backend and
the timers are processed while you call Wait or Poll.

Signed-off-by: Cyril Hrubis <metan@ucw.cz>
build: Update list of exported symbols.

Signed-off-by: Cyril Hrubis <metan@ucw.cz>
spiv: Get rid of the ugly slideshow code, use timers!

Signed-off-by: Cyril Hrubis <metan@ucw.cz>
doc: input: Add GP_Timer and GP_TimeStamp docs.

Signed-off-by: Cyril Hrubis <metan@ucw.cz>
doc: backends: Add GP_BackendAddTimer() docs.

Signed-off-by: Cyril Hrubis <metan@ucw.cz>