add support for multiple secrets (independent agents) on the knock daemon

This allows you to generate more than one pre-shared secret on the knock daemon so that you can distribute the secret and control revocation at a more granular level.  Each additional secret creates one more concurrent authentic knock sequence.

hypd/configuration/configuration.go

@@ -12,7 +12,6 @@ type HypdConfiguration struct {
 	SuccessAction         string `json:"successAction"`         // The action to take for a successful knock, each argument is a separate string
 	TimeoutSeconds        int    `json:"timeoutSeconds"`        // If > 0, once a knock sequence has been successful this value will count down and when it reaches 0, it will perform the TimeoutAction on the client
 	TimeoutAction         string `json:"timeoutAction"`         // The action to take after TimeoutSeconds has elapsed.  only applicable if TimeoutSeconds is > 0, each argument is a separate string
-
 }
 
 // LoadConfiguration opens and parses the configuration file into a HypdConfiguration struct