(TWILL-105) Remove ZKDecoratorService and some pom file fixes

- The ZKDecoratorSerivce is complicates and is not necessarily and have complicated race condition inside
- Most of the functionalities in ZKDecoratorService are moved into AbstractTwillService
  - It uses AbstractExecutionThreadService from guava that simplifies a lot of service+zk related interactions
- The Hadoop secure store related code in AbstractTwillService are moved into AbstractYarnTwillService
- Fixes in the pom.xml
  - There should be one Hadoop version profile that is activeByDefault
  - Increase memory size for unit-test
- Increase test timeout for PolicyPlacementTest