1.1.2: Look in the meta tags for og:image first

If a page has an og:image tag it's probably the best image to use, so if that's there use it instead of parsing all the img tags

1.1.1: Transfer 1 batch request at a time

Temporarily resolves a problem where a batch would fail due to one request inside it failing, which meant sometimes a non-optimal thumbnail being selected.

Will probably try to fix this properly using Guzzle4

Updating for Guzzle 3.5.0 support

v1.1.0

Updated for compatibility with guzzle 3.5.0