Rename serverlist.js, and make it shareable between node server and browser

Add a trick to exports serverlist as a module in Node server, and as a
plain function in the browser.
Create traymenu module, clean init

Moved tray menu create and populate methods out of init.js.
Moved init stuff (var declarations, loading settings, tray menu
creation, watchr creation) out, to a new method in settings module, so
init is as small as possible.
Refactor getServerList() so it can be used by both node server and browser.

Removed NJSgetServerDetails(), and replaced jQuery by plain old js in
getServerDetails().
As apiServer is now accessible directly from getServerList(), we can
stop cascading it through multiple functions (like watch.start(),
template.upload()).
Fixed require('nw.gui') not working, since tray creation has been moved out from init.html.
Implement tray menu refresh after adding a new watched folder

This cleans the current tray menu, reload settings, populate tray menu
and start watching folders.
Misc. cleaning
Updated nconf and watchr modules. This fixes https://github.com/bevry/watchr/issues/28