modularity LLpractice.js and fix some issues
modularity LLpractice.js and fix some issues

package params and functions,only provide useful API

You may use in index file like this:
LLpractice.init('hitmaps/xueyuehua.json','bgm/xueyuehua.json');
LLpractice.resize();
LLpractice.start();
itorr/LLpractice,itorr/LLpractice,itorr/LLpractice