Revit 2015 initial commit

Update CS.props to point to 2015.
Update outdated API methods.
Merge remote-tracking branch 'origin/master' into Revit2015
Update ProtoTestConsoleRunner to 4.5
Update FFITarget to 4.5
Revive alternate context drawing...

For curves and points only now.
Add a Revit_2015 context...

For alternate context visualization.
Merge remote-tracking branch 'origin/master' into Revit2015

Conflicts:
	src/DynamoRevit/VisualizationManager/VisualizationManagerRevit.cs
Add regression case for MAGN-3203
Fix output path for FFITarget project.
More project upgrades to 4.5

Required based on dependencies moving to 4.5
Merge remote-tracking branch 'origin/master' into Revit2015
Remove unused reference.
Remove unused references.
Remove unused references.
Merge remote-tracking branch 'origin/master' into Revit2015
Merge remote-tracking branch 'origin/RevitSubFolders' into Revit2015
Parameterize Revit version in project files.

This will allow us to switch the Revit output paths with one change in
our CS.props file.
Merge remote-tracking branch 'origin/RevitSubFolders' into Revit2015

Conflicts:
	src/Config/CS.props
Update version path in addin.
Remove model open code from ray bounce test.