Update build.gradle

Change versions of customized packages of Red5 Server and Red5 Client from:
red5-client-1.0.2-RC1-MOD.jar to red5-client-1.0.2-RC2-MOD.jar 
red5-server-1.0.2-RC4-MOD.jar to red5-server-1.0.2-RELEASE-MOD.jar
Removed red5-io-1.0.2.jar