Reworking of RiakObject, metadata, and javadoc

Huge WIP commit.
Merge branch '2.x-development' of github.com:basho/riak-java-client into 2.x-development

Conflicts:
	src/main/java/com/basho/riak/client/core/FutureOperation.java
	src/main/java/com/basho/riak/client/core/RiakFuture.java
Fixed RiakFutureListener spelling