Google Drive - Image support added

[micheus]

Since people started to use share images from their Google Drive (GD) I decided to play around with the forum settings and add support to preview the images.

This way, when you use the option to create a link for share in GD it will create a link like this: https://drive.google.com/open?id=0BxuGGuBBD8DXRmE4aVc4YmV4emM

In order to add the image preview here in the forum we must to use the tag gdrive and the image id (spoted in red above):
[ gdrive]<image id>[/ gdrive] (without the spaces)

This is the result: