VISIBLE CHANGES:
- Control interface (/proc/video/ov511/<minor#>/control) implemented.
- Added YUV420P to YUV422/YUYV conversion (to support compression and ttpp).
- Added ov511_mode_init_sensor_regs(). Sets OV7620 to interlaced mode for QVGA
  resolutions, for better quality. Not enabled for other sensors yet.
- New OV7620 initial settings. Improves image quality drastically.
- Setting/getting picture settings improved (especially with OV7620).
- ov511.txt: Minor updates.
- ov511.txt: Changed e-mail address.

BUGFIXES:
- Fixed erroneous error message in YUV420 mode (with compression or ttpp on).
- Fixed bug where ov51x_set_light_freq() could fail to restart ov511.
- Moved video device registration to after device init, to prevent opening of a
  partially initialized device.
- Fixed possible oops if proc file is read after unplug.
- Fixed broken error handling in ov51x_configure() functions.
- ov511.h: Fixed bug in PDEBUG macro.

INTERNAL CHANGES:
- Compression setup code moved to ov51x_init_compression().
- Added individual functions for getting/setting contrast, brightness, hue, and
  saturation.
- Added ov51x_set_auto_brightness(). Not used yet.
- To support control interface, some settings (compress, lightfreq, bandfilt)
  are stored in struct ov511 instead of global variables.
- ov511.h: Added control interface stuff.
- ov511.h: Added auto_brt, auto_gain, auto_exp, compress_inited, lightfreq,
           and bandfilt variables to struct ov511.