Incorporate battery model into Scenario

Enable drawing graphs for battery current and state of charge. Note that the current value is based on the battery data for RP battery.
Add GraphViewCapability to provide graph data for Component, since different component may require different types of graph.
I think there could be some problems with backward compatibility here - since there will be existing Activities in the shared database which were converted to XML based on the previous set of fields, I think these would break with this version of the code for a couple of reasons:

* Since the accessor type is "FIELD", JAXB will (if I remember correctly) try to use reflection to set the value of fields based on what is stored in the XML version of the model. So, when a user loads an old component, fields named "power", "comm" etc will not be found and some sort of exception will likely occur (at minimum, any values in these fields would likely be lost)
* Changing the name from ActivityData to ActivityModel could be similarly problematic (since the underlying implementation may rely on Class.forName or similar)

You should be able to maintain backward compatibility by keeping these fields in place, and special-casing your new methods (getValue and setValue) to look for them (instead of at the map) when appropriate.

One way to check for backward compatibility is to run the version of the scenario plugin currently on master, create some scenarios/activities using these properties, and then shut down and run again with the version of the plugin on this branch, and check to see if there are any exceptions or missing data.