Update blueflood graphite finder with rudimentary support for preagg

Preaggregated metrics have different default attributes than regular
metrics. A more comprehensive solution will need to be devised that
exposes these different values that blueflood calculates. For now, this
change will allow users to graph metrics sent into blueflood using
statsd.
Merge pull request #389 from dlobue/graphite_finder_support_preaggregated_metrics

Update blueflood graphite finder with rudimentary support for preagg
Making Zookeeper integration code more readable.

* Making more variables into `final` so that the state modification is more controlled.
* Adding comments in various places, especially regarding the lock states.
* Adding zookeeper bootstrapping to the test suite, and moving the test out of the integration test (in fact, this test was blacklisted and was never executed).
* Reducing the usage of the mockito whitebox.
* Reducing the amount of shared states, by pulling the scavanger state out of the member variable and storing it within the function scope.
* Removing the usage of `java.util.Timer`.
* Separating out the zookeeper connection wait outside the constructor - that makes the tests more reliable, since having the lock managers in disconnected state is most likely bad.
Updated copyright
Merge pull request #383 from jeeyoungk/jee.zk

Making Zookeeper integration code more readable.
Merge pull request #386 from gdusbabek/make_rollup_delay_millis_configurable

make ROLLUP_DELAY_MILLIS configurable.
First pass to get rid of all the metrics persistence optimizer classes
	- Changed shouldPersist in AstyanaxWriter to use the logic in the StringMetricsPersistenceOptimizerClass
	- Added unit tests to test AstyanaxWriter for metrics persistence
More unit tests for the persistence functionality
Deleting all unnecessary classes
Configuring droppage of string metrics
Added documentation to the tests
Adding support for configuring the tenantids for whom string metrics need to be kept
Addressing review comments
Merge pull request #394 from tilogaat/clean_string_metrics_optimizer

Clean string metrics optimizer
Using getListProperty of the Configuration class
Merge pull request #395 from tilogaat/dropstringmetrics

Drop string metrics
Merge branch 'master' into rax-prod