[2835] Add the data source name option

An optional name of the client in the client list in data source. No
handling done yet, only added to the spec file so it can be set.

src/bin/cfgmgr/plugins/datasrc.spec.pre.in

@@ -63,6 +63,11 @@
                                     "item_optional": false,
                                     "item_default": ""
                                 }
+                            },
+                            {
+                                "item_name": "name",
+                                "item_type": "string",
+                                "item_optional": true
                             }
                         ]
                     }