Fix incorrect log messages in template.py

[cassie-nahar-nasa]

Currently running doorstop publish --verbose all ../public will incorrectly say Copying [...]\templates\html to [...]\template when it should say to [...]\public\template.

Fixed this by changing the log messages to use the template_dir variable instead of building the path again (incorrectly).

This is the same approach already used when logging copying the views subdirectory.