Option to short-press power button. (#56)

Adresses #53 

Please check if we still need the code to "Give the user up to 1000ms to
start holding the power button, and must hold for
SETTINGS.getPowerButtonDuration()" - the power button should be pressed
already when waking up...

Also, decided to return before the delay to wait more to make the
behavior more immediate.

---------

Co-authored-by: Dave Allie <dave@daveallie.com>

src/activities/settings/SettingsActivity.h

@@ -25,7 +25,7 @@ class SettingsActivity final : public Activity {
   const std::function<void()> onGoHome;
 
   // Static settings list
-  static constexpr int settingsCount = 2;  // Number of settings
+  static constexpr int settingsCount = 3;  // Number of settings
   static const SettingInfo settingsList[settingsCount];
 
   static void taskTrampoline(void* param);