Compatibility for node-webkit 0.10.0

Nwk 0.10.0 has two breaking changes for node-webkit-builder
1. The zip packages contain a root directory that needs to be stripped out after unzipping
2. The file list for windows was modified

This fixes those issues in addition to a bit of cleanup and a fix for the deprecated warning that bluebird was giving.

This should fix: https://github.com/mllrsohn/node-webkit-builder/issues/35, https://github.com/mllrsohn/node-webkit-builder/issues/34, https://github.com/mllrsohn/node-webkit-builder/issues/33, https://github.com/mllrsohn/node-webkit-builder/issues/32