Add slider to control video quality

This reverts commit 953969acc04e8ec1f9731dce770d187599e37e6d.
It also adds a checkbutton below the slider which enables
automatic video quality adjustment (and is on by default).

The slider now has a range of 0 to 100 and sets both the bitrate
and quality parameter of each codec by getting the min and max
values of both and scaling the set value.

Change-Id: I307e541c6e30c432ab5452bba2af9c2f069d79d9
Tuleap: #215
diff --git a/pixmaps/ic_high_quality_black_24px.svg b/pixmaps/ic_high_quality_black_24px.svg
new file mode 100644
index 0000000..6f030a1
--- /dev/null
+++ b/pixmaps/ic_high_quality_black_24px.svg
@@ -0,0 +1,4 @@
+<svg fill="#000000" height="24" viewBox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg">
+    <path d="M0 0h24v24H0z" fill="none"/>
+    <path d="M19 4H5c-1.11 0-2 .9-2 2v12c0 1.1.89 2 2 2h14c1.1 0 2-.9 2-2V6c0-1.1-.9-2-2-2zm-8 11H9.5v-2h-2v2H6V9h1.5v2.5h2V9H11v6zm7-1c0 .55-.45 1-1 1h-.75v1.5h-1.5V15H14c-.55 0-1-.45-1-1v-4c0-.55.45-1 1-1h3c.55 0 1 .45 1 1v4zm-3.5-.5h2v-3h-2v3z"/>
+</svg>
\ No newline at end of file
diff --git a/pixmaps/pixmaps.gresource.xml b/pixmaps/pixmaps.gresource.xml
index 23c4b62..a143e94 100644
--- a/pixmaps/pixmaps.gresource.xml
+++ b/pixmaps/pixmaps.gresource.xml
@@ -16,5 +16,6 @@
 	<file alias="mute_video">ic_videocam_off_black_24px.svg</file>
 	<file alias="pause">ic_pause_black_24px.svg</file>
 	<file alias="end">ic_clear_black_24px.svg</file>
+	<file alias="quality">ic_high_quality_black_24px.svg</file>
   </gresource>
 </gresources>