JSON/YAML Backed Spoofing of Servers

It would be useful for local development and for continuous integration for csh_ldap to be able to spoof server data. Once this is implemented applications (as well as csh_ldap) would be able to add automated testing for their csh_ldap usage.

I'm not sure how we'd want to structure the local spoof data, but at first thought JSON or YAML would probably be sufficient. As an argument to the CSHLDAP constructor we could just add a `spoof_file` named parameter that bypasses making a server connection.