Dynamic reloading of handler classes with revised step definitions

[nickebbutt]

At present when you export a handler from a remote component, it's necessary to restart the component when you recompile to change step patterns (the step method itself can often be modified and reloaded in debug mode, but the values of step annotations cannot be).

The goal is to enable a mode where the handler classes can be reloaded at runtime from a separate class loader, and expose a better API for adding steps dynamically