Adding upstream version 3.1.0+dfsg.

Signed-off-by: Daniel Baumann <daniel@debian.org>

tests/yanglint/modules/modaction.yang

@@ -0,0 +1,26 @@
+module modaction {
+  yang-version 1.1;
+  namespace "urn:yanglint:modaction";
+  prefix ma;
+
+  container con {
+    list ls {
+      key "lfkey";
+      leaf lfkey {
+        type string;
+      }
+      action act {
+        input {
+          leaf lfi {
+            type string;
+          }
+        }
+        output {
+          leaf lfo {
+            type int16;
+          }
+        }
+      }
+    }
+  }
+}