gennai 2014/11/15版に対応

* JDK1.7対応
* initスクリプト改修
 * root以外での実行を不可
 * 多重起動チェック
* README.md修正
11/18版対応
Added overview sentences.
Added lead sentences at Getting Started and gathered used apps info.
Revised a getting started with our simple example.
Merge pull request #3 from tf0054/master

Revised README.md for genn.ai github top.