start working on User and Group classes

- User and Group has been moved to 'models' directory
- removed UserPass struct (passwords fields were put to User struct)
not working yet, we need support for binary blobs in morm

winixd/core/session.h

@@ -40,7 +40,7 @@
 #include <ctime>
 #include <map>
 #include "error.h"
-#include "user.h"
+#include "models/user.h"
 #include "plugindata.h"
 #include "rebus.h"
 #include "textstream.h"