Ignore .DS_Store
API: Use config / extension APIs

Overhaul of spam protection to use an extension on Form rather than the SpamProtectorManager. More fluent interface and easier to replace the built in spam protection api with an alternative.
Add basic tests
Add travis
ID can be used to validate object
API Refactor field mapping from FormSpamProtectionExtension into SpamProtector
API EditableSpamProtectionField may now be configured for spam on an individual field basis
Translations added
Merge pull request #11 from tractorcow/pulls/refactor-mapping

API Refactor field mapping into SpamProtector / UserForms extension
Added @tractorcow's akismet module link
API Re-introduced ability to insert spam field before another existing field
Merge pull request #13 from tractorcow/pulls/insertbefore

API Re-introduced ability to insert spam field before another existing field