Allow 0.10.0 failures.

See #534 for the 0.10.0 reasoning.

Also, I changed to use `0.10` and `0.11` instead of the specific
versions as recommended by the Travis folks. This will give use the
latest version in that series provided by the Travis VM (and is likely
what we want anyways).
Merge pull request #535 from rjackson/handle-0-10-0-failures

Allow 0.10.0 failures.