changed: Don't allow change of volume amplification with passthrough audio
settings: fix updating skin-related settings spinners
properly reset skin-related settings after changing the current skin (fixes #14595)
sync to current internal FFMpeg code
fixed, video playback glitches for avcC content
1) update internal ABI headers
2) removed aml legacey vars and structs
3) add debug filedump of data sent to amcodec.so
4) remove internal avCC convert, CBitStreamConverter handles it.
   this was cause of glitch, a rare double convert attempt that
   resulted a malformed NAL which faulted the hw decoder.
Merge pull request #3385 from Montellese/fix_skin_theme

properly reset skin-related settings after changing the current skin (fixes #14595)
[configure] enable TLS support in ffmpeg via gnutls
[depends] add gnutls
try to fix gmp compilation on android
only set gmp ABI on 32bit linux
[WIN32] added gnutls 3.2.3 to our mingw environment and the runtime dlls to system/players/dvdplayer
[WIN32] added: build ffmpeg with gnutls support. Force extracting during unzipping.
[depends] - for darwin add xz as dependency for allowing extraction of tar.xz files
[depends] - build native xz and tar on osx aswell (needed for extraction of xz tarballs - introduced with gnutls)
[gnutls/config.site] - gnutls needs gl_cv_func_gettimeofday_clobber=no for compiling on darwin
[depends] - make the tar-native executable accessable via ARCHIVE_TOOL_NATIVE
[gnutls] - for compiling on osx and ios we need to disable-nls - also we need to use our native tar for extracting the xz tarball
[gnutls] - if gnutls is there don't compile OSXGNUReplacements as they are duped in gnutls already
[xcode] - link against gnutls and related deps
[ios/atv2/depends] - disable gmp, nettle and gnutls for now until we get gmp to build for ios