* pull things that don't rely on HDFS in hbase-server/FSUtils into hbase-common/CommonFSUtils
* refactor setStoragePolicy so that it can move into hbase-common/CommonFSUtils, as a side effect update it for Hadoop 2.8,3.0+
* refactor WALProcedureStore so that it handles its own FS interactions
* add a reflection-based lookup of stream capabilities
* call said lookup in places where we make WALs to make sure hflush/hsync is available.
* javadoc / checkstyle cleanup on changes as flagged by yetus
Signed-off-by: Chia-Ping Tsai <chia7712@gmail.com>