feat!: implemented multigame support (#34)

Reviewed-on: #34
Co-authored-by: Janis <janis.e.20@gmx.de>
Co-committed-by: Janis <janis.e.20@gmx.de>

knockoutwhistweb/app/logic/user/SessionManager.scala

@@ -0,0 +1,14 @@
+package logic.user
+
+import com.google.inject.ImplementedBy
+import logic.user.impl.BaseSessionManager
+import model.users.User
+
+@ImplementedBy(classOf[BaseSessionManager])
+trait SessionManager {
+  
+  def createSession(user: User): String
+  def getUserBySession(sessionId: String): Option[User]
+  def invalidateSession(sessionId: String): Unit
+
+}