Add Honeywell TCC temperature logging post

It's not perfect. Todo list:
* Replace header photo
* Replace graph images with individual full-sized ones (with no gaps)
Add Honeywell TCC + cacti setup post

Also not perfect. Todo list:
* Get a more "interesting" lead graph image
* Replace the final two graph images with full-width ones (with no gaps)
Remove as
Update config for a newer jekyll!