Allow a user to pause using eye gestures

[gavinhenderson]

Is your feature request related to a problem? Please describe.
Users cannot pause using eye gestures alone, this means they have to rely on another person to pause it.

This could be annoying if a user wants to stop communicating but keeps triggering their switch accidently.

Describe the solution you'd like
Users should be able to set a configurable eye gesture to cause EyeCommander to sleep and wake

Additional context
This requires some careful thought about unpausing. To pause we can easily do 'eyes closed for x amount of time' but to unpause we can't do 'open for x time'.

Message NG once done

[willwade]

I'm with this - but I wonder if we have another way of pausing too. From the software they actually use. See if they are switch scanning they just want to access a button that says "Pause EyeCommander" - and that then sends a keystroke, or a Windows Message (or something) to the app to pause.