Rework our JNI interface and add ffmpeg bindings for AVC decoding (WIP)

src/com/limelight/nvstream/av/audio/OpusDecoder.java

@@ -2,7 +2,7 @@ package com.limelight.nvstream.av.audio;
 
 public class OpusDecoder {
 	static {
-		System.loadLibrary("nv_opus_dec");
+		System.loadLibrary("nv_av_dec");
 	}
 	
 	public static native int init();

src/com/limelight/nvstream/av/video/AvcDecoder.java

@@ -0,0 +1,13 @@
+package com.limelight.nvstream.av.video;
+
+public class AvcDecoder {
+	static {
+		System.loadLibrary("nv_av_dec");
+	}
+	
+	public static native int init(int width, int height);
+	public static native void destroy();
+	public static native int getCurrentFrame(byte[] yuvframe, int size);
+	public static native int getFrameSize();
+	public static native int decode(byte[] indata, int inoff, int inlen);
+}