Added chapter markers in a chapter text track in mp4 files.

Added chapter markers in a chapter text track in mp4 files.
This option is turned off by default.  It can be turned on in the CLI by specifying a "-m" or "--markers" option.  it is not yet enabled as an option in the Mac GUI.
These chapter tracks are only detected by QuickTime if the file extension is .m4v.  If the extension is .mp4, the chapter text track is ignored.
To this end, I have made test.c detect .m4v as a file extension for mp4 too.
This change has required a substantial change to the mp4v2 library patch.  Until the precompiled contrib binaries are updated by Prigaux, try doing "./configure" and then "./jam" (which will build the native contribs, but fail to build UB versions of the apps), and then try "make internal" to compile a native version of the apps.

git-svn-id: svn://localhost/HandBrake/trunk@440 b64f7644-9d1e-0410-96f1-a4d463321fa5