Instead of using a keyboard event which ends up getting spoken
use SIGUSR2 to tell orca to stop speaking.
Not sure why cargo added windows bits to Cargo.lock here...
Add functionality for various actions by sending left control key
press and release events.
Also add to steamosctl trigger_action support.
NOTE: Stop Speaking action should be changed to use orca's new dbus
api once that's packaged.
Orca has no API, so use keyboard events to trigger specific actions
like sticking to focus mode, browse mode, etc.
Also add new get and set methods to steamosctl for mode.
Add ScreenReader1 interface to xml to enable/disable using screen
reader.
Implements getting and setting pitch, rate, volume, enabled.
Restarts orca when any of the above properties are changed.
Load values from orca user-settings.conf
Use systemd unit to start/stop/restart orca.
