Added state perstistance

- Define new state directory to hold the last dns update config and push it into the config, default to state/
- Refactoring, move updaterequest into service and out of webapp. Keep only the form parsing there. Specifically, move the processing code into the service package, it shouldn't be in the webapp.
- Add code to load and save the last updaterequest into a state file (watch out to keep the possibly unhashed password out of it).
- Add a command line option to load all available state files given the current configured user list from the command line.
- Refactor user configuartion loading to separate it from user authentication, claen up the code.
- We now require the username in the config, to make handling it in state updates easier. This will allow easier transition to DB style storage anyway.
- Update .gitignore

service/config.go

@@ -20,6 +20,7 @@ type configDNS struct {
 
 type configUsers struct {
 	ConfigDir string
+	StateDir  string
 }
 
 var C config
@@ -32,6 +33,7 @@ func SetConfigDefaults() {
 	viper.SetDefault("Service.DNS.Server", "127.0.0.1:53")
 	viper.SetDefault("Service.DNS.DefaultTTL", 60)
 	viper.SetDefault("Service.Users.ConfigDir", "users/")
+	viper.SetDefault("Service.Users.StateDir", "state/")
 }
 
 func LoadConfig() {
@@ -47,6 +49,12 @@ func LoadConfig() {
 	} else {
 		C.Users.ConfigDir = filepath.Join(viper.GetString("ConfigDir"), path)
 	}
+	path = viper.GetString("Service.Users.StateDir")
+	if filepath.IsAbs(path) {
+		C.Users.StateDir = filepath.Clean(path)
+	} else {
+		C.Users.StateDir = filepath.Join(viper.GetString("StateDir"), path)
+	}
 }
 
 func (obj *config) PrettyPrint() string {