Update /ja/index.html and /en/index.html article code samples.

Fiexed to use the latest API in the article code samples.
Correspond to the latest API for creating the instance of ScriptProcessorNode

The old API for creating the instance of ScriptProcessorNode is "createJavaScriptNode" method.
But, The latest API is "createScriptProcessor" method.
Therefore, this update added code for wrapping this difference.
Merge pull request #1284 from Korilakkuma/my-work

Update /ja/index.html, /en/index.html and /static/samples/meter-node.js