Having GST_DEBUG_CATEGORY and GST_DEBUG_CATEGORY_EXTERN together
might lead to 'undefined symbol' problems. This commit moves
the _EXTERN to a separate new file.
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.
* decouple image capturing from image post-processing and encoding
* post image-captured message after image is captured
* post preview-image message with snapshot of captured image
Default view finder sink in camerabin is autovideosink which doesn't
support xoverlay iface. If application decides to use another sink
that supports xoverlay, then it can use the interface directly.
Application developers won't know right away which module an interface comes from,
and may assume that it is covered by the usual GStreamer API guarantees, so make
it as clear as possible that this particular API is still subject to change
(should have done that with other libraries in -bad before too really).
