Add names and descriptions to the inputs and outputs of core functions and subroutines.

[drwhut]

This will allow GUI editors to directly get the input and output names from the Decision library.

This would also allow us to automatically update the user manual reference if we had a way to export the data.

[drwhut]

Will probably need to refactor the code once it's merged into development.

[drwhut]

Also need to finally decide what is const and what isn't.