9gag media download helper per Minhazul Hayat Khan

=> Adds a option to download 9gag images and videos to download them in .mp4 or .jpg format, instead of the .webp and .webm format, which is the typical option when using the 'save video as' or 'save image as' default options in the browser.
=> Also automatically adds the post's title as the file name.

**Instruction on how to use:**

• To get the most out of this add-on, open a post/gag in a separate tab then download the image/video by pressing right click on the image/video and selecting the "Download 9gag" option.
• A download pop up should open prompting you to select the location.
• The file name will be identical to the title of the post.
• Both images and videos can be downloaded from from main page as well. But the title as file of the videos will work only when the video/gif is opened in a separate tab.