Adds BashCommands.waitForPortFree
BashCommands.waitForPortFree: fix for centos
Incorporate #1358 comments: BashCommandsIntegrationTest
Merge pull request #1358 from aledsage/feature/BashCommands.waitForPortFree

Adds BashCommands.waitForPortFree
Fixing/investigating LoadBalancing policy failure

- motivated by test failure in jenkins
  (LoadBalancingPolicySoakTest.testLoadBalancingManyItemsQuickTest)
- improving error reporting on failure
- decrease pause-time between rebalances (was default 100ms; now 1ms)
- fix warning of duplicate MockItemEntity management
- tidy to remove compile warnings