#134 Fixed clover build failures

Clover wouldn't work if the jar is not on the classpath of the machine
building it or if the clover jar doesn't exist in the expected place
before running the clover targets. Fixed this the same was as fixed by
the checkstyle targets with the same problem.
Merge pull request #135 from ExpediaInc/fix-first-build-failure

#134 Fixed clover build failures