Addressed most review feedback on BindException fixes.

.classpath
- fixed error I introduced.

*RebalanceTest.java
- refactored to reduce cut&paste code
- added comments and one TODO about attempting a proper fix wrt BindExceptions later.

ServerTestUtils.java
- renamed method back to startVoldemortServer
- added 'throws BindException'

test/unit/voldemort/scheduled/StreamingSlopPusherTest.java
- added comment clarifying why this test is hard to harden against BindException issue