v1.1.0

• Rename the headerauth setting to ep_headerauth. For compatibility with existing configs the headerauth setting is still honored, but a deprecation warning will be printed.
• Defer to the next authentication plugin (or to the default behavior if there is no other authentication plugin) instead of failing if authentication does not succeed.
• Update URLs from rhansen/ep_headerauth to ether/ep_headerauth.
• Minor code cleanups.