MAGN-4201 Solar Analysis

This PR includes all the functionality in the Solar Analysis user story. It is a large PR and requires assets that are external to this repo to do a full live test. Specifically, it requires the Dynamo Solar Insolation package which is available on request.

http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-4201

Require Merges:

- [ ] Revit 2015

PTAL:

- [ ] @pboyer
- [ ] @Steell 
This should probably just return `InternalElement.Id` as opposed to tracking an `ElementId` as a separate field (and remember to keep it in sync). This change actually went in to fix a symptom of a bug where `ReferencePlane` was not keeping `InternalElement` and `InternalElementId` in sync.