[Jolo-develop] Addition of int hashcode() override in MapObject

[Mike Y. <you...@us...>]

Perhaps it would be good to have MapObjects override the int hashcode()
method of Object for the providing of a hashcode for hashcode creation for
syncing.

Should we override Object's hashcode or have MapObject's implement their own
hashcode method with a different name and stuff?

Originally it was thought that an MapObject's hashcode would be a hash of
it's Externalized Stream.....However, it may be valuable for things such as
moveable objects to provide a more rounded value for things such as X and Y.
To help prevent out of sync errors.  Externalize would have to return exact
values....maybe we could have a getHash type of method that hashed non exact
values.

What do you all think?

Mike