Running the server without signingSecret causes no error until attempting to login

[DennisRas]

Steps to Reproduce

• Install the server
• Don't change any configuration (keep signingSecret empty)
• Run the server
• Install and/or run your client
• Login

Expected Behavior

• Normal login

Actual Behavior

• No warning or message in the client
• Server error below

(node:11880) UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 1): Error: secretOrPrivateKey must have a value
(node:11880) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

Possible Solution

• Create a warning in the client if server isn't responding (because of the error)
• Create a warning on the server that signingSecret isn't set and is needed when running
• Create a default signingSecret value on post-install Generate signingSecret on post-install #115