Add streams to connection.
Add custom pool.
Add send-timeout.
Ensure connection with minimum refcnt is head of seq.
Bring back pool stripes.
Correct usage of throw*
Cleanup.
Add support to trace requests/responses.
Use logger in `Pool`.
Restrict tracing output to 160 bytes.
Revert back to only reap connections with refcnt = 0.

I.e. on timeouts resources are put back into the pool, their refcount
is decremented and their timestamp updated. The pool considers resources
valid if there is only a `Timeout` while in use. Consequently the reaper
only checks resources with refcount 0.
Add `maxTimeouts`.

A configurable threshold which - if exceeded - causes the connection to
be destroyed. As streams which produced a timeout are lost, we keep
accumulating timeouts and do not reset t0 0 or decrement the count.
Log info message on max. timeouts.
Include connection in open/close log messages.
Replace `Time` module with `auto-update`.

Also use `Conrol.Reaper` in `TimeoutManager`.
Handle 'Void' results from schema queries.

Since Cassandra 2.0.10/2.1.1, schema queries using "if not exists" clauses may return a void result.

cf. https://issues.apache.org/jira/browse/CASSANDRA-7600
Merge pull request #3 from romanb/schema-noop

Handle 'Void' results from schema queries.
Update to cql-3.0.
Begin implementing node discovery
Remove `Client` monad and pass cluster enviroment around.