Begin work on a `DiscoveryPool` implementation.
Dry-coded the auto-discovery pool. Unit tests are next.
When auto-discovering, skip nodes that have empty token lists as they
are probably not in the ring for real. Their entries are zombies sticking
around in the system.peers table because Cassandra.
Update dependencies & lock them down to minor version numbers.
Removed the connection lifespan tests since we have removed the feature.
Renamed the test suite to 'monitor' since that what it now tests.
Changed its assertion style from chai.assert to must.
Fixed the one failing monitor test, which was failing because we
changed how pings work. The clients are now responsible for pinging
themselves. When they fail, they emit a health event that their owning
pool listens for & reacts to.
Hack out the pre-test check for setting cql versions for now.
Checkpoint: rewriting the tests to not use chai-as-promised makes
them both clearer & 100% more likely to pass. Down to 8 failing
tests to rewrite.
All CQL3 tests now pass.

All but one fix was a simple rewrite of the test to avoid using
chai-as-promised. The fix that mattered was in the after() handler:
made connection.close() emit its close event.
All the cql2 tests now pass.
Just three failing thrift tests to rewrite!
Mocha now says: 158 passing (12 seconds)
Sadly coverage is now at 83%, but at least the entire test suite is now
passing when run locally.

Let's see what Travis says.
Update the readme badges with the new location of the repo.
Test on localhost on Travis, please.
At last! Unit tests for the discovery pool. These must be run by hand for the
moment; I need to distinguish between Travis and localhost invocations.
Document DiscoveryPool & expose it in the module exports.
If we're on Travis, use localhost instead of my integration testing ring.
Argh. Localhost.