Updated Greek translation.

Refs: #1680.
Add back part of a string that was mistakenly removed from the Greek translation.
Graph builder: improve debug output.
MpaDecFilter: fixed DTS bitstreaming after 9697fd0793.
French translation: Fix two inverted strings.
Apply the "Repeat" option after "Play next in the folder".

The repeat option will now take effect after the next file in the folder was played (similarly to what happens for playlist items).

This commit fixes #978.
include MIPS headers only when ARCH_MIPS is defined
remove the unneeded MIPS files
update ffmpeg (n0.8-19451-gb56e029)

Notes: broken atm because our custom files need to be updated too

* libavcodec/h264_dxva.c
* libavcodec/h264_recov.c
* libavcodec/vc1_dxva.c
update ffmpeg/config.h