reverting proguard change to avoid java.lang.UnsupportedClassVersionError when compiling from java 6
reverting proguard change to avoid java.lang.UnsupportedClassVersionError when compiling from java 6

getlantern/lantern-java,lqch14102/lantern,getlantern/lantern-java,lqch14102/lantern,lqch14102/lantern,lqch14102/lantern,lqch14102/lantern,getlantern/lantern-java,getlantern/lantern-java,getlantern/lantern-java,lqch14102/lantern,getlantern/lantern-java,getlantern/lantern-java,getlantern/lantern-java,getlantern/lantern-java,lqch14102/lantern,lqch14102/lantern,lqch14102/lantern