load options with stream mode, option file can be json/ini/yaml/ion file
npm install options-stream#Options Stream
``javascript
var os = require('options-stream');
var options = os({ // code default options
a: 1
b: 2
}, 'etc/options.default.json' // project default options
, 'etc/options.hostname.ini' // host options
, 'etc/hotfix.yaml' // hotfix options
, 'etc/hotfix.ion' // overwrite options
);
``