[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
Merge pull request #3193 from wsnipex/ffmpeg-gnutls

enable TLS/SSL support in  ffmpeg