Fix yz tests

This fixes  the YZ integration tests that were failing by adding new pauses.

The behavior of YZ has slightly changed, apparently, where now setting bucket props immediately after creating an index will fail telling you the index doesn't exist. Pausing for 10 seconds seems to do the trick.

This can be tested via:

`mvn clean install -Pitest,default -Dcom.basho.riak.yokozuna=true -Dcom.basho,riak.buckettype=true`

With search enabled and the `test_type` bucket type created and activated. 

fixes #422 
This is still a non-deterministic way of doing this. Other client tests add a wait loop, and verify that that the index exists before continuing. Sure, generally speaking it should work after 1 second, but there no no guarantee at all.