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.
Fixed link of masthead to go current language code.
Replaced old link of contributor's guide with github's.
Merge pull request #1286 from cwdoh/hotfix.add.lang_code.to.masthead_link

Fixed link of masthead to go current language code.
Automatically updating the calendar
Merge pull request #1284 from Korilakkuma/my-work

Update /ja/index.html, /en/index.html and /static/samples/meter-node.js
Automatically updating the calendar
Automatically updating the calendar
Automatically updating the calendar
Changing template a tad
Send some links to web fundamentals
Automatically updating the calendar
Update index.html

typos
Adding theme color
Merge branch 'master' of github.com:html5rocks/www.html5rocks.com
Automatically updating the calendar
Automatically updating the calendar
Merge pull request #1290 from xarus01/master

Update index.html
Automatically updating the calendar