Bug 710827 - add robotium.jar to m-c under build/mobile/robocop; r=jmaher

build/mobile/robocop/README

@@ -0,0 +1,9 @@
+Robocop is a Mozilla project which uses Robotium to test Firefox on Android devices.
+
+Robotium is an open source tool licensed under the Apache 2.0 license and the original 
+source can be found here:
+http://code.google.com/p/robotium/
+
+We are including robotium-solo-3.0.jar as a binary and are not modifying it in anyway 
+from the original download found at: 
+http://code.google.com/p/robotium/