[CMake] A variable to identify the Dart model type?

[Nathaniel Waisbrot (Cont ARL/CISD)]

I have a script, external to the rest of the CMake build, which performs
some dashboard submission.  I'd like to have it perform that submission
*only* when ctest has been invoked as part of 
'make (Nightly|Continuous|Experimental)', not 'make' or 'make test'.

Is this possible?  I haven't been able to find any variables or
functions that make reference to the Dart model.