Fixed bug involving serial number filtering
and added a test to the eunit cases

Squashed commit of the following:

commit e0f27294c2518cec942d85fc0bf5b83b81ae2d84
Author: Samvit Ramadurgam <samvit@asana.com>
Date:   Tue Jul 30 16:36:30 2013 -0700

    made the test pass

commit 73c0c96cbef0edba3fba2f2197ab54bd8a970cff
Author: Alex Davies <alexd@asana.com>
Date:   Tue Jul 30 16:09:59 2013 -0700

    Work on a test to demonstrate the bug with old messages
Fixed Subscription code
Updated Version
Removed the extra export_all's
Exposed the run function on the kraken_benchmark module
Decreases the default bounded queue size from 1MM to 100K to decrease memory usage
Increment version #
Removed log which was making the log4erl process do too much Synchronous IO
Exposed two more functions to the RShard API and incremented the version number
Update kraken.app.src
Lowered bounded queue bound to 1000
Documentation Fix
Kraken now respondes with memcached 'NOT_FOUND' if the registration serial was too old for the subscribe to retroact properly
Merge branch 'master' into lower-bound
Fix bug where the horizon of a particular connection is never updated
This gives the effect that the original Register command's horizon is used for all subscribes, which eventually caused REGISTRATION_TOO_OLD_RESP for sufficiently old clients.
Merge branch 'lower-bound'
Raise messages stored to a level where simple tests of retroactivity are likely to succeed
Fix a bug where register is used before the first published messages, and the corresponding subscribe is after
This caused an erroneous "register too old" error