vf_lut: switch to an AVOptions-based system.
vf_overlay: switch to an AVOptions-based system.
vf_pad: switch to an AVOptions-based system.
Merge commit '20b46f8f4fff6aeeab9ea418dc359eda8887ced6'

* commit '20b46f8f4fff6aeeab9ea418dc359eda8887ced6':
  vf_lut: switch to an AVOptions-based system.

Conflicts:
	doc/filters.texi
	libavfilter/vf_lut.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '9087eaf193b8ce99c41352064a81916fa66adb49'

* commit '9087eaf193b8ce99c41352064a81916fa66adb49':
  vf_overlay: switch to an AVOptions-based system.

Conflicts:
	doc/filters.texi
	libavfilter/vf_overlay.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>
lavfi/overlay: remove dupe initializer

Signed-off-by: Paul B Mahol <onemda@gmail.com>
Merge commit '40c885c589808455a1c4b473509f1e6cd4908f55'

* commit '40c885c589808455a1c4b473509f1e6cd4908f55':
  vf_pad: switch to an AVOptions-based system.

Conflicts:
	doc/filters.texi
	libavfilter/vf_pad.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>