Changelog
* Adds option to delete tags, with a new permission on `roles.py` for it: `manage_tags`;
* Uses `django-crispy-forms` to auto generate some forms with error handling;
* Fixes bug where URLs of tags were not encoded correctly for some characters (like "&");
* Fixes bug where implications could be uppercase;
* Changes visuals of buttons and adds more straight-forward functions on forms;
* Adds posts relationships like parent, child and siblings;
* Fixes icons and titles on the staff page;
* Adds some search operators: `order`, `score`, `rating` and `status`;
* Adds Mod Queue and Post Flagging system;
* Adds icons on the sidebar of posts;
* Adds option for staff members to hide comments, and a new permission on `roles.py` for it: `manage_comments`;
* Adds verification for file size on downloading or uploading files with new variables for verifying on `settings.py`: `BOORUNAUT_MAX_SIZE_FILE`, `BOORUNAUT_INITIAL_UPLOAD_TIMEOUT` and `BOORUNAUT_MAXIMUM_UPLOAD_TIMEOUT`;
* Changes the `custom_code` to be a variable in `settings.py` (`BOORUNAUT_INCLUDE_HEADER_CODE`) instead of a customizable option on the staff page;
* Creates dedicated ad block as a variable in `settings.py` (`BOORUNAUT_ADS_CODE`) that has the option to not show on questionable or explicit posts (variables `BOORUNAUT_ADS_ON_QUESTIONABLE` and `BOORUNAUT_ADS_ON_EXPLICIT`.