added default that match openssh ssh_config defaults
added commenting
fixed issue with array munging
removed debug messages
updated tests to match the default of not allowing hostbased auth
Restore empty hash behavior for loading nonexistent files
Let auth methods be added or removed, and ensure there are no duplicates
Clone default auth methods to avoid modifying defaults
Add support for ChallengeResponseAuthentication keyboard-interactive
Fix session test to work with new default auth_methods
Add config tests for auth parsing
Merge pull request #144 from liggitt/auth_methods_config_parsing

Correctly interpret /etc/ssh_config Authentication settings based on openssh /etc/ssh_config system defaults