Remove now useless files and update README

Author: thiblahute

README

@@ -1,22 +1,8 @@
-This the official GStreamer integration testsuites implementation repository.
-Those testsuites are meant to be used with GstValidate available in the
-gst-devtools[0] repository
+This the official GStreamer media files to be used with the default integration
+testsuites.
 
-This repository includes both media files (available in medias/)
-that will be retrieved from the web using medias/get_files.py and several
-testsuites (available in testsuites/) to be used with gst-validate-launcher[1].
+This repo only contains the media files and is used as a submodule of the
+`gstreamer` repository.
 
-By default, gst-validate-launcher --sync will retrieve that repository to run
-the default testsuite (namely validate and ges testsuites from testsuites/validate.py
-and testsuites/ges.py)
-
-For any USAGE documentation, you should refer to gst-validate documentation and
-in particular to:
-
-    $ gst-validate-launcher --help
-
-Note that this repository uses [git-lfs] so you will need to install it before cloning.
-
-[0] http://cgit.freedesktop.org/gstreamer/gst-devtools/
-[1] https://gstreamer.freedesktop.org/data/doc/gstreamer/head/gst-validate/html/gst-validate-launcher.html
-[git-lfs] https://git-lfs.github.com/
+Note that this repository uses [git-lfs] so you will need to install it before
+using it.