Update:     compile 'com.android.support:appcompat-v7:21.0.2'
Update: classpath 'com.android.tools.build:gradle:1.0.0-rc4'
Upgrade: classpath 'com.android.tools.build:gradle:1.0.0'
Delete: copyright from gradle script
Downgrade:          classpath 'com.android.tools.build:gradle:0.14.4'
Downgrade:          classpath 'com.android.tools.build:gradle:0.14.4'