Make `rfc_compliant` function available in module as well
Use `rfc_compliant` function while sanitize email address
Add `falsy` fixture to produce false values for tests
Add wrapper to produce safe email headers
Make mail subject RFC 2822-compliant string
Update version number
Merge pull request #7 from vitalk/make-subject-rfc-compliant

Make subject RFC 2822-compliant string.