shims.d.ts should never be included in simulator

sim/visuals/neopixel.ts

@@ -1,6 +1,5 @@
 /// <reference path="../../node_modules/pxt-core/built/pxtsim.d.ts"/>
 /// <reference path="../../libs/core/dal.d.ts"/>
-/// <reference path="../../libs/core/shims.d.ts"/>
 /// <reference path="../../libs/core/enums.d.ts"/>
 
 namespace pxsim.visuals {
@@ -240,4 +239,4 @@ namespace pxsim.visuals {
         }
         public updateTheme(): void { }
     }
-}
+}