Update gcc_build.

  - Update gcc-4_9-branch-update patch for PR61214.
  - Delete unneeded files to reduce toolchain size.
  - libiconv/libintl/bzip2/zlib: Build only shared libraries.
Update buildscripts.

 - ffmpeg.sh: Use openjpeg2 instead of openjpeg.
 - ffmpeg.sh: Add --disable-binaries to speex configure options.
 - flac.sh:   Use svn repository instead of git one.
 - lsmash.sh: Fix installing dll.
buildscripts & gcc_build: Add -static-libgcc.

This is for eh of i686 bins, which are built with MSVC.
Cleanup basefile system.