Add webview's utility js files to MANIFEST.in

Author: ales-erjavec

MANIFEST.in

@@ -9,6 +9,7 @@ recursive-include Orange/canvas/application/workflows *.ows
 
 recursive-include Orange/widgets *.png *.svg
 recursive-include Orange/widgets/_highcharts *.js *.css *.html
+recursive-include Orange/widgets/utils/_webview *.js
 recursive-include Orange/widgets/utils/plot *.fs *.vs *.gs *.obj
 
 recursive-include distribute *.svg *.desktop