FAQ on changing data granularity

added cause this question is asked a ton of times on google group and i had a similar question and had to resort to the forums cause there was no doc.
fix dynamic config bug
Fixed the issue of batch ingestion with indexing service to hdfs end up with the path of metadata in mysql missing "hdfs://host" prefix. The detail describe can be found here: https://groups.google.com/forum/#!topic/druid-development/ofvSxiPpCxI
fix spatial indexing with multi spatial dims
make the selection strategy in rtr extendable
Merge pull request #757 from pdeva/master

FAQ on changing data granularity
Fixes #761
Merge pull request #767 from metamx/fix-search

Fix NPE when searching  real-time with a non-existing dimension
fix regression in test
Merge pull request #759 from metamx/fix-dynamic-config

fix dynamic config bug
TaskLogs fixes and cleanups.

- Fix negative offsets in FileTaskLogs and HdfsTaskLogs.
- Consolidate file offset code into LogUtils (currently used in two places).
- Clean up style for HdfsTaskLogs and related classes.
- Remove unused code in ForkingTaskRunner.
Merge pull request #769 from metamx/task-logs-fixes

TaskLogs fixes and cleanups.
address cr
Merge pull request #765 from metamx/fix-spatial

fix spatial indexing with multiple spatial dims
Merge pull request #760 from flowbehappy/fix-hadoop-index-path-prefix

Fixed the issue about the path's prefix after batch ingestion with indexing service to hdfs
upgrade jetty and workaround for half open connection

Upgrade jetty and set acceptor priority delta to -1
 to give priority to servicing connections already accepted rather than
opening new connections.
Merge pull request #770 from metamx/jetty-conn-issue-fix

upgrade jetty and workaround for half open connection
address cr
fix #730 - memory check throws exception if fails

fix exception handling, do not catch ProvisionException
address cr again