mediacontrol_core.c: remove handling of the start position for mediacontrol_start, it crashes the application

* backport [17230] DnD unicode fixes in wxWidgets

 - DVR-ms support
 - TTA support
 - [17142] add 5.1 support for flac
 - [17158] fixes for max amount of audio channels
 - [17180] lower SDL_image priority to fix mjpeg
 - [17194] require libgcrypt explicitly

 - h264 packetizer changes
 - add mp2v fourcc to libmpeg2 decoder
 - shoutcast TV fix for the OS X GUI
 - fix for time in http

Backport rev [17063]. Correctly count childern of a node. The previous code counted the endpoints too, which gave a too high children count.

 - [16941] (partially) fix bug in variable value inheritence
 - [16942] (edited) border options of mosaic filter
 - [16958] fix raw m4v and h264 detection
 - [16971] avoid using the C++ STL. This gets rid of weird crashes in the vector template
 - [16974] fixed invalid memory access in stream_ReadLine()
 - [16996] fixed a bunch of memleaks
 - [16997] fixed a memleak in asf
 - [16998] fixed memleaks in slave/sub handling
 - [17000] Add RV20 fourcc
 - [17001] and [17007] fix errors in [16996]
 - [17008] memleak in XML xtag parser
 - [17019] memset fix in Ty module