Fix race condition in verify_dvv_repl.

Fetch the sink object on each iteration of the wait_until, just in case
that the entire set of siblings didn't make it across the repl link.
This also gives read-repair a chance to happen, in case the version the
sink wrote didn't make it to all replicas.
Adjust test to ensure that essential concurrency =< n_val
Use result of fold in ensemble_basic3

When resuming vnodes we need the proper pid from the previous suspend.
Use the result of the fold to get the right pids.
Don't try to resume pids that don't exist
Fix failure on slow replication

This changes the test assertion so that it retries fetching the value
from the second cluster until it is the expected value, at which point
the test will either pass if the sibling count is reasonable or fail if
it is too damn high.
Merge pull request #715 from basho/bugfix/sdc/dvv-race

Fix race condition in verify_dvv_repl.
Merge pull request #716 from basho/bugfix/ensemble_basic3

Use result of fold in ensemble_basic3
Verify the list of stats keys is complete

    * Checks the list of stats keys returned from the HTTP endpoint
    is complete.
    * Modifies reset-current-env to properly clean dependencies when a
    full clean is requested
    * Adds logging to verify_riak_stats to explain the addition steps
    being performed