Added optional Actor and ActorBase
new extensions package
new util package
Request => RequestBase
Request is now an interface
Requests with no arguments are now variables
Made Mailbox and MailboxFactory more configurable
Merged pull request from dallaybatta
Future possible optimisations require that the Message instances be created by the Message queue itself.
Merge remote-tracking branch 'upstream/master'

Conflicts:
	src/main/java/org/agilewiki/pactor/Request.java
	src/main/java/org/agilewiki/pactor/impl/MailboxImpl.java
Merging the javadocs changes with latest code.