remove initialize method, fix warning message 'explicit call to +initialize results in duplicate call to +initialize'

Author: wangchauyan

SDK/OpenWebRTC.h

@@ -37,10 +37,4 @@
 
 @interface OpenWebRTC : NSObject
 
-/**
- *  Initializes OpenWebRTC. Should preferably be run inside your AppDelegate's 
- *  initialize method to ensure OpenWebRTC has enough time to set things up.
- */
-+ (void)initialize;
-
-@end
+@end