Add target "run_tests" to allow us to run junit tests.
Add target "run_tests" to allow us to run junit tests.

Removed "clean" from "init" target so that we won't be rebuilding every time.  If you want to rebuild 
from scratch you must do "ant clean".

Added "jar" dependency so that now target 'compile_tests' works.

Added some variables and refer to them instead of using constants.

Grace, please review.

googlegsa/manager.v3,googlegsa/manager.v3,googlegsa/manager.v3