configure.ac: Adding examples/switch/Makefile

configure.ac: Adding examples/switch/Makefile

Original commit message from CVS:
2004-01-11  Julien MOUTTE  <julien@moutte.net>

* configure.ac: Adding examples/switch/Makefile
* examples/Makefile.am: Adding examples/switch
* examples/switch/Makefile.am: Adding switcher example.
* examples/switch/switcher.c: (got_eos), (idle_iterate),
(switch_timer), (main): Adding an example demonstrating switch usage
with 2 videotestsrc showing different patterns.
* gst/switch/gstswitch.c: (gst_switch_request_new_pad),
(gst_switch_init): Fixing switch with the new caps system.