idl - add idl_check.ysl2 - a static analyser for interface descriptions

idl/idl_check.ysl2

@@ -0,0 +1,20 @@
+// IDL Check
+// Static analysis of code written in pEpACIDLang IDL
+// no output - no problems
+
+include yslt.yml2
+
+tstylesheet {
+    include idl_api.ysl2
+
+    // The idl-api owns the root template and executes validation
+    // of the interface description.
+    // Errors will be printed to stdout.
+    // After successful validation, the idl-api applies the
+    // template called "pEpACIDLang"
+
+    template "pEpACIDLang" {
+        > No problems found.
+    }
+}
+