Auto-orient improvement + remote images improvement

Rather then adding autoOrient on all of the ImageUtil methods, I've added
an extra method that can be used for this. `autoOrient` simply brings
to much overhead and a performance degradation to execute it on each
image operation.

For example, doing an `autoOrient` once on the source preview image rather
then on each single one, results in a performance improvement of around
36 percent.

I've also added `autoOrient` to the profile pictures so that they can be
displayed correctly in the browser.

We're now better handling flickr, slideshare and vimeo inputs.
If an image has no thumbnail, it will be ignored.