Adding pre-roll to VideoCacheThread, and making video & audio threads wait for the isReady() method before playing. Also fixed an audio bug where our internal buffer was not being cleared on seek. Removed some unused caching from Clip, and did some minor refactor on FrameMapper/Clip cache clearing.

src/FrameMapper.cpp

@@ -655,24 +655,24 @@ void FrameMapper::Close()
 
 		// Close internal reader
 		reader->Close();
-
-		// Clear the fields & frames lists
-		fields.clear();
-		frames.clear();
-
-		// Mark as dirty
-		is_dirty = true;
-
-		// Clear cache
-		final_cache.Clear();
-
-		// Deallocate resample buffer
-		if (avr) {
-			SWR_CLOSE(avr);
-			SWR_FREE(&avr);
-			avr = NULL;
-		}
 	}
+
+    // Clear the fields & frames lists
+    fields.clear();
+    frames.clear();
+
+    // Mark as dirty
+    is_dirty = true;
+
+    // Clear cache
+    final_cache.Clear();
+
+    // Deallocate resample buffer
+    if (avr) {
+        SWR_CLOSE(avr);
+        SWR_FREE(&avr);
+        avr = NULL;
+    }
 }