gh-95 Update the MongoDB driver to use a singleton Mongo instance for
each test client.

Add a control (via properties) for the number of connections the Mongo
instance will create/use.
gh-95 Update the MongoDB driver version to 2.9.0.
gh-102 Minor fix so the classpath path separator is OS independent
gh-100 Time clean up and count it for hbase as update.

* Time the cleanUp of a DBWrapper
* For HBase this clean up should also be counted as an update.
gh-47 Fix an issue with JDBC scans

JDBC scans did not instruct the driver to use a specific fetchsize,
resulting in most cases in an OOM; add support for setting fetchsize.

Also add support for disabling autocommit on the JDBC connections,
mostly because Postgres for example doesn't support setting fetchsize
without disabling autocommit.
Updated .gitignore and fabric configs.
Merged changes from original YCSB from github branch
Fixed Aerospike client version and set of enabled modules.
Failing the Couchbase
Fixed failover and start commands.
Created commands to shutdown and up Couchbase.
Implemented kill/start for Couchbase.
Some minor changes
Some minor changes. Added check before atrm. Increased time delta.
Added failover commands for other databases.
Before pull
Merge branch 'master' of thumbtack.beanstalkapp.com:/ycsb
Added sample to merge timeseries
Before pull
Merge branch 'master' of thumbtack.beanstalkapp.com:/ycsb