feat(calendar(web)): allow to change the classification of an event

UI/WebServerResources/scss/core/structure.scss

@@ -54,4 +54,12 @@ html * {
   &:last-child {
     margin-bottom: 0;
   }
-}
+}
+
+// Remove "leave" transition
+// Convenient with a ng-switch statement or when using multiple ng-if statements that are mutually exclusive
+.sg-no-transition {
+  .ng-leave {
+    display: none;
+  }
+}