Simplified how the 'makefile' determines the suffix of the 'rst2*' programs. ...

Removed dependency on 'tren' for file renaming.
Cleaned up python and shell skeletons for consistent and clearer help banner.
Commented out config file parsing in python skeleton.
Documented requirement for 'tconfpy' to use this python parsing logic.
Added handlers for the demo X, Y, and Z options in the shell skeleton.

Moved '.py' suffix detection for 'rst2*' programs from 'tmkproject.sh' ...

to the 'makefile' skeleton.  This ensure the check is performed on
every run of 'make' not just when the project is initially created.

Factored substitution tokens out of the main code so that the user ...

can add their own.