Use new validations adding
Fixing integration with dm-validations v1.2.0
Validation is working with dm 1.2.0. Tests are passing
Merge the fixes to implement dm 1.2 validations from: https://github.com/kot-begemot/dm-paperclip/commits/fix_for_dm_1_2_0
Fix tests that where not passing

Conflicts:
	.gitignore
	Gemfile
	Rakefile
	dm-paperclip.gemspec
	lib/dm-paperclip.rb
	lib/dm-paperclip/attachment.rb
	lib/dm-paperclip/processor.rb
	test/attachment_test.rb
	test/helper.rb
	test/integration_test.rb
	test/iostream_test.rb
	test/paperclip_test.rb
	test/storage_test.rb
	test/thumbnail_test.rb
Fix path interpolation for attachments to make them Sinatra-compatible
Commit extracted from: https://github.com/inbeom/dm-paperclip/commit/c3bb759755dffa8bae0d0d7c1a1ae33160d89dbb
Fix gemspec
Add uuid interpolation to hide model id if required
Add validator to check attachment geometry
Merge pull request #30 from fsaravia/master

New fix for dm-validations 1.2 and Sinatra