Add support for wrapping the build in UMD syntax.

config/ol-debug.json

@@ -1,3 +1,4 @@
 {
-  "exports": ["*"]
+  "exports": ["*"],
+  "umd": true
 }

config/ol.json

@@ -1,5 +1,6 @@
 {
   "exports": ["*"],
+  "umd": true,
   "compile": {
     "externs": [
       "externs/bingmaps.js",
@@ -59,7 +60,6 @@
     ],
     "compilation_level": "ADVANCED",
     "warning_level": "VERBOSE",
-    "output_wrapper": "(function(){%output%})();",
     "use_types_for_optimization": true,
     "manage_closure_dependencies": true
   }