ENYO-3078: Signing keys correctly saved in project.json and displayed in the UI.

Link to the JIRA ticket: https://enyojs.atlassian.net/browse/ENYO-3078

Tested on Chrome Canary (Windows 7)
Enyo-DCO-1.1-Signed-off-by: Rafik Adiche mahmoud-rafik.adiche@hp.com