Revert "baseparse: don't leak caps in gst_base_parse_process_streamheader"

This reverts commit 5e8b4bf085180f7a4c7ae6ec0f525baeaedd4df8.

This causes refcounting criticals in the baseparse unit test.
fakesrc: mark the pattern property as unused

Revert the previous commit which removes the pattern property of fakesrc because
doing so will break ABI. Bringing the property back but marking it as unused
in the property string.

https://bugzilla.gnome.org/show_bug.cgi?id=737683
tests: baseparse: set_sink_caps vfunc should't take ownership of the caps

https://bugzilla.gnome.org/show_bug.cgi?id=737762
baseparse: don't leak caps in gst_base_parse_process_streamheader

https://bugzilla.gnome.org/show_bug.cgi?id=737762
inputselector: fix printf format

The padcount is uint. Also add comments to the instance vars.
input-selector: small code cleanups

Rename TIMESTAMP -> PTS. Move a var down to the scope where it is used. Use
g_queue_free_full().
input-selector: extract some common code into helpers
inputselector: fix compilation