Adds a new plugin for setting the timeout before the display is turned
off. The timeout value, in seconds, is controlled by the
"display_idle_timeout" option.
Setting the value to 0 disables the timeout and leaves the display
always on.
Change-Id: Ibc7dbad3b1ce6ec06ff0d50d937409914d18685a
Implements: blueprint display-idle-timeout-plugin
Co-Authored-By: Stefan Caraiman <scaraiman@cloudbasesolutions.com>