Fix minor bugs: log file close, typo, JSON field consistency

- Add defer logfile.Close() to prevent file descriptor leak
- Fix typo 'Incomming' -> 'Incoming' in log message
- Change JSON tag 'Misc' to 'misc' for consistency with sMsg

internal/misc/types.go

@@ -56,7 +56,7 @@ type rMsg struct {
 		GoodMorning int64  `json:"good_morning,omitempty"`
 		Msgformat   int64  `json:"msg_format,omitempty"`
 		Username    string `json:"username,omitempty"`
-	} `json:"Misc"`
+	} `json:"misc"`
 }
 
 /* vim: set ft=go noet ai ts=4 sw=4 sts=4: */