AbstractAdapter wasn't delegating `binmode` or `binmode?` to the
underlying @tempfile object. `binmode` is useful for cases where the
Adapter object gets handed on to another library expecting an `IO`
object holding image data. We ran into this with Prawn and people using
`prawnto` in conjunction with Paperclip. Prawn wants to ensure the `IO`
is in binmode for embedding the image data.

Use hexdigest to ensure that tempfile names will be a reasonable length.  Remove illegal filename characters check since it is no longer relevant when doing a hexdigest on the filename

pry-debugger doesn't compile on JRuby, and we're really only using that
locally.

Base64 encoded data-uris can contain newlines, make sure we handle
them correctly.

Content Type errors were incorrectly being set as an array on the base
attribute rather than being set individually as strings.

Copying attribute validation failures up to the root object breaks the
validate_attachment_presence_matcher when other paperclip validations
have failed.  This fixes this bug.

Added the sample .mp4 file from Apple's QuickTime sample page:
http://support.apple.com/kb/ht1425

You can either specifiy :restricted_characters or you can define your
own :filename_cleaner object. This object needs to respond to #call and
takes the filename that will be cleaned. It should return the cleaned
filenme.