Updated to utilize the Fakku API & more

- Updated the grabinfo script to use the Fakku API speeding up the
process of grabbing info about new mangas.
- Made the filter be case-insensitive
- Fixed loadingtrail appearing twice sometimes
- Time since a manga was added is now tracked internally and should be
updated each time the extension is opened.
- Changed the way errors are handeled slightly as a result of using the
Fakku API now instead.