Make dependency-check execution a JDK8 activated profile (#254)
Make dependency-check execution a JDK8 activated profile (#254)

- dependency-check>=4.0.0 will not run with JDK7. So we conditionalize
the check in a profile thats only activated if JDK>=1.8
- Added comment about why dependency-check-maven is in a profile
- Set skip=true globally, but false in JDK>=8 Profile

confluentinc/common,confluentinc/common