Other changes:
* added dependency on SDL for testcard
* TODO: consider more cleanups (removing all X checks from
  configure.ac etc.)
* dropped check for GLU (no longer needed)

* minor code cleanup in QT

* there was some irrational glibc corruption when copying into
  SDL_Surface v210 data

* it was unstable somehow, anyway cmdline string still works

* removed busy waiting
* allowed to compress any video that is divisible by 4 in both
  dimensions
* add optional argument to '-c' specifying number of compressing threads

* do not build perf on gcc < 4.1 (current Xcode's default gcc)

* frames are not generated now, instead a pointer moves accross 2 copies
  of image

* dropped unnecessary options from main

Conflicts:

	ultragrid/src/main.c

+ possibility to send new formats

Conflicts:

	ultragrid/src/video_display.c
	ultragrid/src/video_display/xv.c

* Xv
* kona -> quicktime
* dxt -> gl
* renamed gl_sdl to gl

+ multiple changes -- run thread moved to main (required for glut),
  DXT merged to GL etc.

* adjusted timeouts
* new sync
* API - returned Makefiles (ignored by default)

* some build system improvements

* finished 4K support
* some improvements (locking etc.)

* drop unused functions

* there are many of those - see log