Accept single style for #height, #width
Update hash syntax
Pin development dependencies: rake, rspec
Cleanup, speedup spec

* Lazy load fixtures as private methods instead of always creating and
setting ivars
Remove unused code

post_process happens before save.
The _meta value is always set, so there is no reason to execute an
update afterwards.
Further, for new records, update_all does nothing since `instance.id`
is nil.
Add update test, use consistent equality check syntax

* Test style and default style height and width
* Rename test style to :thumb so it doesn't conflict with "small" image
Remove redundant respond_to? check; instance_write does that
Silence paperclip log in tests
Version 0.6.0