Removed unused imports.
Random PMD fixes.
Ignoring Eclipse generated folders for PMD and CodePro AnalytiX
Removed legacy code, used for a one off test/poc.
From looking through PMD report, I removed useless parentheses.

Some of the code might make the code more readable. In that case, I will bring back the changes made and ignore the rule for those instances.
Added final keyword to method's parameter.
Ignoring PMD file generated by Eclipse.
Fixed typo.
Declared constructor parameters final.
Changed verbiage from each to vertex. Added curly braces on if checks.
Avoid modifiers which are implied by the context. Found by PMD
Added FIXME documentation surrounding using an interface to hold constants.

I tried generics, failed. Will revisit in the future.
Declared variables final where applicable.
#7 Removed useless semi colon.
#7 Removed unnecessary continue statement in loops, replaced with equivalent logic.
#7 Whitespace.
#7 removed useless null check.
Merge branch 'feature/pmd-fixes' into develop