Simple demo BWL app

Fetch list of queues and corresponding priorities:
curl localhost:1974/queues

Enqueue "some data" into the "single" queue:
curl -X PUT -d "some data" localhost:1974/queues/single --header "Content-Type:text/plain"
Add a note about using truncate out of context
Merge pull request #24 from wajam/manu-truncate-warning

Add a note about using truncate out of context
Revert Bwl.definitions to original visibility.
Fix stupidity...
Merge pull request #23 from wajam/manu-demo

Simple demo BWL app
Fix computation of the start timestamp when starting bwl after log cleanup
Merge pull request #26 from wajam/manu-fix-start-after-cleanup

Fix computation of the start timestamp after log cleanup
Merge pull request #25 from wajam/clement-delayed-tasks

Add a unit test for MemoryQueue + fix totalTasks stat
Fix peristent queue restart after log cleanup (bis)
Better support for zookeeper cluster
Demo integration with ZK and ConsistencyMasterSlave
Enqueue script
Keep track of the queue last item id

Do not rely on TransactionRecorder anymore as its current consistent timestamp is computed with a delay and we need the last item id in real-time.
Merge branch 'master' into manu-demo2
Scalariform reformating
Fix persistent queue start after log cleanup
Merge pull request #27 from wajam/manu-demo2

Replication and zookeeper integration
Add support for delayed tasks in MemoryQueue