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