docs: list compatible io.js versions
docs: list compatible io.js versions

RoseTHERESA/connect,senchalabs/connect,wghust/connect,qitianchan/connect,khalerc/connect,lian774739140/connect,keenwon/connect,llwanghong/connect,RickyDan/connect,mi2oon/connect,mi2oon/connect,gtomitsuka/connect,austincitylimits/connect,liuwei9413/connect,behind2/connect,tanveer12332/connect,khirayama/connect,chinazhaghai/connect