Increments version
Eliminates sleeps in test suite.

Sleeps had been introduced into test suite to account for lags within
S3 when putting and deleting objects. Now, when making HTTP calls to
verify the presence or deletion of an object at a URL, we only sleep
when we don't get the result we expect. We sleep for a short period,
and if we still don't get what we're expecting, we sleep longer, using
a sort of exponential backoff system, up to some specified maximum
wait time (10 seconds by default). This has sped up several
integration tests and dramatically sped up
test_unit_project_remote.rb.