Add --fast option for running tests
Document --fast testing
Fix code of conduct label
Removed context weirdness

This breaks anyone who subclassed hashers for hashing customization.
Remove the _*Hash namedtuple weirdness
Add support for latest PyPy beta

You can install the latest PyPy beta using ``brew install --devel pypy``
on OS X using homebrew.
Apparently travis uses an outdated pypy version
Add more documentation to BCryptHasher
Add more documentation to PBKDF2Hasher
Document PasswordHash
Include encoding information in .create() docs
Document BCrypt.{format,parse}
Document PBKDF2Hasher.{parse,format}
Add default .format implementation
Refactor encoding in Hasher
Document Hasher
Document SaltedDigestHasher.{format,parse}
Improve *.format documentation
Document HMACHasher.{format,parse}
Improve PasswordHasher.from_config_file