Configure auto-lock timer

[grctest]

Is your feature request related to a problem? Please describe.

There's an automatic timer which if no activity is detected then it locks the wallet and returns the user to the login screen.

There's times where its' been too eager to logout when I'm trying to line up a transaction to prompt/broadcast.

Describe the solution you'd like

Enable the user to set a longer auto-logout timer.

Describe alternatives you've considered

Increase the static auto-logout timer by 30 seconds.

Additional context

This is just a bit annoying sometimes, not a problem otherwise.

[brekyrself]

When it does the auto time out, the app also takes you back to the main screen which may confuse the user "where did my wallet go." The user must click either "create a new wallet" or "restore wallet" & cancel for it to return to the main screen showing the already created wallet.

Windows 10:

[grctest]

Yeah this is a known issue: #16

clicking "alt -> top file menu -> refresh page" gets around this, but you're right that sometimes (not always) when auto logged out it appears like it's forgotten the wallet...