Check PMD Flags
Merge branch 'master' of https://github.com/azatris/cs4218

# By Mingxia Liu
# Via Mingxia Liu
* 'master' of https://github.com/azatris/cs4218:
  More test cases for CommTool

Conflicts:
	test/sg/edu/nus/comp/cs4218/impl/extended2/COMMToolTest.java