Update builds to use gradle 2.12

 Updating Red5 triggered updating of ffmpeg jars for screensharing.

 Change dependencies to build against latest red5 to upgrade to java 8

bbb-video/build.gradle and bigbluebutton-apps/build.gradle uses the latest SNAPSHOT version of bbb-common-message

 - stop the stream only if it hasn't been stopped yet

   a way to detect that webcam stream stopped server side because when the client's connection
   to bbb-video is disconnected due to network issue, the notification that the stream stopped
   from the client side can't be sent to the server.

 - update red5 to bring in fix for connections not cleanedup properly which may be cause OOM Exception

STEPS
cd ~/dev/tools
wget http://services.gradle.org/distributions/gradle-1.7-bin.zip
unzip gradle-1.7-bin.zip
ln -s gradle-1.7 gradle
vi ~/.profile

export GRADLE_HOME=$HOME/dev/tools/gradle
export PATH=$PATH:$GRADLE_HOME/bin

source ~/.profile