Deleting unnecessary code from Demo 214 (#256)

Author: francisco-milan

src/z2ui5_cl_demo_app_214.clas.abap

@@ -4,15 +4,8 @@ class z2ui5_cl_demo_app_214 definition
 
 public section.
 
-  interfaces IF_SERIALIZABLE_OBJECT .
   interfaces Z2UI5_IF_APP .
 
-  data:
-    BEGIN OF screen,
-        input1 TYPE string,
-        input2 TYPE string,
-        input3 TYPE string,
-      END OF screen .
   data CHECK_INITIALIZED type ABAP_BOOL .
   PROTECTED SECTION.