Correct the exclude function and more...

Hi Xeor,

This pull request has commits for the following things:

* Fixes a minor typo in the docstring of make_tags().
* Gives the path a file is being included from in the debug output.
* Corrects the checks to ignore dotfiles/folders, as we want to use it if the option is set to true.
* Only makes the tags if the file is not being included from the tags folder. Without this check, if you have your `content_folder` in /home/user/pictures and `tags_folder` in /home/user/pictures/tags, you'll face recursive tags, which is not wanted. Feel free to try without the conditional to see what I mean.

Merge what you like :). Cheers,