ENYO-963-node-webkit: better test for presence of window
use path.resolve('') when __dirname is not defined

__dirname is undef in node-webkit
warn user to not close node server window in node-webkit
ENYO-963-node-webkit: protect against undef env._
ENYO-963-node-webkit: remove log that breaks node-webkit on windows
ENYO-963-node-webkit: remove question mark in comment
ENYO-963-node-webkit: move process exit handler into mopUp function
ENYO-963-node-webkit: destroy node children processes when server window is closed