Move from nw.js to Electron

[dreampiggy]

The reason why we need to move is that nw.js is lack of some great feature (auto update, ) and we have on an really old version (nw.js v0.12.3) which may contains some bugs and the render process is slow comparing to Electron.

Electron community has a large number of plugins and solution out-of-box. It has a widely use in the open source platform. But nw.js is now become more and more out-of-date and lack of some documents or awesome feature.

Since this application is not really need to be compatible to Windows XP. We can use Electron instead to build cross-platform application. And the codebase does not heavily depend on nw.js runtime(NaCI or something), it mostly use raw HTML & CSS to draw Broswer UI and directly call to sub process command line. Maybe it's not hard to move.

I will keep this issue here for future roadmap.

[hankzhu91]

exciting !