Fix warnings and clean up javadocs in sal-akka-raft

Fix warnings and clean up javadocs in sal-akka-raft

Fixed a lot of checkstyle warnings and cleaned up javadocs for the remaining
classes sal-akka-raft. Most of the warnings/changes were for:
 - white space before if/for
 - white space before beginning brace
 - line too long
 - period after first sentence in javadoc
 - missing <p/> in javadoc

Change-Id: I99a3cd08af10d46acecd0e22f04d54b95e2287d9
Signed-off-by: Tom Pantelis <tpanteli@brocade.com>