Fixes issue with those that have a thumbnail size set to something other than the XenForo default of 100.
Improved the code regarding the thumbnail creation and very small animated gif's.
Also put in a fail safe if thumbnail dimension cannot be read.
In version prior to v1.5, if an image exceeded a maximum dimension in only one direction, the resize code only resized the image in one direction.
In v1.5 images will never exceed the allowed maximum width and height settings.
Fixed code so that large images now resize to max dimensions.
Fixed code error dealing with temporary directory.
Fixed bug where converted attachments were shown as a link. Fixed database query to update thumbnail_width and height correctly.
Found bug dealing with temporary image directory.