Power management signals

[shermp]

There were discussions on pgaskin/NickelMenu#124 about using the signals from N3PowerWorkflowManager to notify scripts/programs when resuming from sleep etc. It's probably best to continue the discussion over here.

For reference, the available signals are:

aboutToSleep()
resumingFromSleep()
resumedFromSleep()
aboutToPowerOff()
aboutToReboot() 

Pinging @marnovdm @NiLuJe

[marnovdm]

Yes this seems like a better place, thanks for opening this! I (unintentionally) hijacked the original issue post a bit anyway 😄

Not sure if I can contribute anything here, as I'm not really familiar with C++, and I'll be on holiday for the next couple of weeks so it'll be a while before I get back to this issue.