add fastclick;
add login via token, remove devise's token_authenticatable;
users are able to log into EasyJobs web page from the Android app with
a token since the web page is responsive and can be viewed on mobile
devices. devise's token_authenticatable is not perfect because it
accepts token params on every page and the devise official will soon
deprecate the token_authenticatable, so I write a little but similar
token auth code. the token param now only takes effects on api pages.