Add queue_size option for batch method

 * Add Cassandra::Batch for holding the queue
 * Add flush_batch to Cassandra
 * Add tests
Fix code block in README
Bump version, add changelog entry for #164
Aded 1.1 support
Bump test timeout

Several people have hit this now
Small doc changes for 1.1 support
Update manifest for 1.1 support
Reduce duplicate code between versions

Everyone 0.8+ has counters, don't need to duplicate

Going forward this should be factored better/differently
Add .travis.yml for builds of 1.1, 1.0 and 0.8 on 1.9.3 and 1.8.7.
Wait until Cassandra starts listening.
Making multi_get_columns get everything in one request

* Also correcting get and multi_get's comments to be less confusing, since they do NOT accept a list of columns or sub_columns
Bump version and update changelog
Set thrift_client_options in the tests to get rid of intermittent TransportExceptions on Travis.
Leave the default exception_classes for retries.
Add 1.2 support
Test 1.2 on travis
By default drop_keyspace should use current keyspace