Move include directives for gst-libs into GST_PLUGINS_BAD_CFLAGS,
and fix all the Makefiles that use it. This is so that all the
include directories are added in the proper order: first the
directories in srcdir/builddir, then gst-plugins-base dirs, then
gstreamer dirs. If the order is wrong, installed headers may be
used instead of local headers and/or uninstalled headers from -base.
Adds the brand new asfmux plugin, containing 3 elements:
asfmux, rtpasfpay and asfparse. This plugin was developed
as a GSoC 2009 project, with David Schleef as the mentor and
Thiago Santos as the student.
