NCS-59 Create Load tests (#2)

Added a load test and and slight change in structure. To execute type:

Run the load test:
  ./gradlew.bat gatlingRun --simulation simulations.LoadTestSimulation -PbaseUrl=https://st.nowchess.janis-eccarius.de
  -PauthToken=<token> -PmaxUsers=20 -PrampDuration=60

  Run smoke test:
  ./gradlew.bat gatlingRun --simulation simulations.SmokeTestSimulation -PbaseUrl=https://st.nowchess.janis-eccarius.de
  -PauthToken=<token>

---------

Co-authored-by: LQ63 <lkhermann@web.de>
Reviewed-on: #2
Reviewed-by: Janis <janis-e@gmx.de>

src/gatling/scala/simulations/LoadTestSimulation.scala

@@ -0,0 +1,20 @@
+package simulations
+
+import base.BaseSimulation
+import endpoints.BoardEndpoints
+import io.gatling.core.Predef._
+
+import scala.concurrent.duration._
+
+class LoadTestSimulation extends BaseSimulation {
+
+  private val maxUsers      = sys.props.getOrElse("maxUsers", "10").toInt
+  private val rampDuration  = sys.props.getOrElse("rampDuration", "60").toInt
+
+  setUp(
+    BoardEndpoints.all.map { endpoint =>
+      scenarioFromEndpoint(endpoint)
+        .inject(rampUsers(maxUsers).during(rampDuration.seconds))
+    }: _*
+  ).protocols(httpProtocol)
+}