noVNC: Disable COPYRECT and prefer TIGHT_PNG

There seems to be an unresolved screen corruption issue with the Qemu
VNC COPYRECT encoding implementation. [1] Comment it out from the
client's preferred encoding list and, since Qemu VNC supports it, always
prefer TIGHT_PNG over TIGHT, for performance reasons.

[1] http://patchwork.ozlabs.org/patch/32165/

Changelog

@@ -11,13 +11,15 @@ repository and have aligned versions.
 v0.16.1
 =====
 
+Released: UNRELEASED
+
 Astakos
 -------
 
 * Include additional validation checks in project modification form to ensure
   members limit is always set lower or equal than total limit.
 
-* Prevent members limit from automatically set to unlimited in project
+* Prevent members limit from automatically being set to unlimited in project
   modification form.
 
 * Exclude terminated projects from responses of project list and user quota
@@ -28,6 +30,8 @@ Cyclades UI
 -----------
 
 * Improve handling of terminated projects in reassign view.
+* Remove the COPYRECT encoding from the preferred noVNC client encodings, and
+  prefer TIGHT_PNG by default.
 
 
 Stats

snf-cyclades-app/synnefo/ui/static/snf/extra/noVNC/include/rfb.js

@@ -48,9 +48,9 @@ var that           = {},  // Public API methods
 
     // In preference order
     encodings      = [
-        ['COPYRECT',         0x01 ],
-        ['TIGHT',            0x07 ],
+        //['COPYRECT',         0x01 ],
         ['TIGHT_PNG',        -260 ],
+        ['TIGHT',            0x07 ],
         ['HEXTILE',          0x05 ],
         ['RRE',              0x02 ],
         ['RAW',              0x00 ],