Add support for dependecy injection and RMI

As pivot application devoloper, I would like to have support for dependency injection in Pivot. My requirements are:

• support for field injection (at least)
• support for @PostConstruct methods
• support for @RuntimeScoped classes - only one instance may be constructed during Runtime. Usefull when one needs share injected instances.
• in relevant cases, inject dependencies also into namespace.

I implemented prototype of this functionality, source codes including unit tests and sample application are included. The dependency injection is implemented in proposed org.apache.pivot.beans.injection package.

Please consider adding this functionality in future Pivot release.