Add a whole lot of stuff

For details, examine each individual commit. Here's an overview:

* Use the print function instead of the print statement
* Some Python 3 compatibility for file loading.
* Look for login info in the same directory as main.py, instead of a hard-coded path.
* Readded fetching the username from a config file, since testing is kinda hard when you can't login.
* Removed mail functions; now we just examine the bot's most recent post to figure out what has been done.
* Added a function to make posts.
* Close the configuration files after reading them.
* Add a .gitignore file to always omit login info from commits.