Move "require 'alaveteli_file_types'" into the initializer
Avoid an FoiAttachment validation failure under Rails 3

Under Rails 3, the uudecoded FoiAttachment in this test
fails validation at the self.save! in
IncomingMessage.parse_raw_email, although the FoiAttachment
has been correctly created and saved to the database in
_uudecode_and_save_attachments.  Forcing a reload=true on
self.foi_attachments fixes this.

Thanks to Louise Crow for finding the fix for this problem.