Fix broken nashorn/samples

jjs -fx barchart_weather.js
Caused by: java.lang.RuntimeException: java.io.IOException: Server returned HTTP response code: 401 for URL: http://api.openweathermap.org/data/2.5/forecast?q=chennai,india&units=metric&mode=json

jjs -fx colorfulcircles.fx
Caused by: fx:bootstrap.js:47 TypeError: Cannot load script from colorfulcircles.fx
Doesn't work in JDK8 either

jjs -fx datepick.js
Caused by: datepick.js:48 ReferenceError: "Scene" is not defined
Works in JDK8

jjs -fx jsonviewer.js
Caused by: java.lang.RuntimeException: java.io.IOException: Server returned HTTP response code: 401 for URL: http://api.openweathermap.org/data/2.5/forecast/daily?q=Chennai&mode=json&units=metric&cnt=7`
Doesn't work in JDK8