tools/gst-inspect.c: Add --print-plugin-auto-install-info option to gst-inspect, so we can introspect plugin files an...

Original commit message from CVS:
* tools/gst-inspect.c:
(print_plugin_automatic_install_info_codecs),
(print_plugin_automatic_install_info_protocols),
(print_plugin_automatic_install_info), (main):
Add --print-plugin-auto-install-info option to gst-inspect, so we can
introspect plugin files and get machine-parsable output that corresponds
to the last bit of the missing-plugin installer string (small gotcha:
doesn't take into account ranks).