First implementation of simulcast, adds VP8 simulcast to video engine.

Changed API to RTP module
Expanded Auto test with a test for simulcast
Made the video codec tests compile
Added the vp8_simulcast files to this cl
Added missing auto test file
Review URL: http://webrtc-codereview.appspot.com/188001

git-svn-id: http://webrtc.googlecode.com/svn/trunk@736 4adac7df-926f-26a2-2b94-8c16560cd09d

src/modules/video_coding/main/source/codec_database.h

@@ -182,7 +182,8 @@ protected:
     /**
     * Create an internal Encoder given a codec type
     */
-    VCMGenericEncoder* CreateEncoder(VideoCodecType type) const;
+    VCMGenericEncoder* CreateEncoder(const VideoCodecType type,
+                                     const bool simulcast) const;
 
     void DeleteEncoder();
     /*