Add BatchMetricsQueryHandler and tests

Add RollupTestUtils
Refactor plot request parsing logic into its own class
Change MetricData to also contain 'type' of metrics
Changes to serializers for JSON output
Add HTTP endpoint & handler for batched metrics
Use enum for MetricData types
Send out max limit as part of response error message
Change type from 'numeric' to 'number'
Merge pull request #143 from lakshmi-kannan/bf_add_multi_fetch_support

Add batch metrics fetch support
Keep compiler happy
Merge pull request #151 from lakshmi-kannan/bf_build_fix

Keep compiler happy
fix NPE in Locator.hashCode()
Sometimes, two reads can happen in less than 5 milliseconds
Merge pull request #153 from gdusbabek/avoid_null_in_locator_hashcode

fix NPE in Locator.hashCode()
Fix assert so that tests pass on openJDK6 (bug in ArrayBlockingQueueImplementation in openJDK6)
Merge pull request #154 from lakshmi-kannan/bf_build_fix

Sometimes, two reads can happen in less than 5 milliseconds
Add multi-fetch support to changelog
Merge pull request #156 from lakshmi-kannan/add_multi_fetch_to_CHANGES

Add multi-fetch support to changelog