Help: Improve wording of CMAKE_CURRENT_FUNCTION_LIST_DIR docs

The original wording was somewhat confusing in talking about rendering of
templates. While technically correct, a less experienced user may not know
that terminology. The wording has been updated to more clearly describe the
example usage.

The old way of implementing the example is not "bad", it was the only way to do
things before the CMAKE_CURRENT_FUNCTION_LIST_DIR variable was added.
The example has been updated to remove the Bad/Good captions to reflect this.
Indentation of the examples was also fixed to make them conform to the guidelines.