List Tutorials

Provided comprehensive set of samples around list manipulation functionality. More can be added later.

This should be a good reference for how to model samples to be shipped with Dynamo, with respect to layout, clarity, and documentation (notes).
It's really not obvious why this works :)

Consider being more explicit:
e.g. something along the lines of 
 var clonedList = list.Clone();
clonedList.Append(item);
return cloned List