Idle handling for dpms/lockscreen et al

Swayidle handles idle events and allows
for dpms and lockscreen handling. It also
handles systemd sleep events, and can
raise a lockscreen on sleep

Fixes #541

swayidle/swayidle.1.scd

@@ -0,0 +1,61 @@
+swayidle (1)
+
+# NAME
+
+swayidle - Idle manager for Wayland
+
+# SYNOPSIS
+
+*swayidle* [options] [events...]
+
+# OPTIONS
+
+*-h*
+	Show help message and quit.
+
+*-d*
+	Enable debug output.
+
+# DESCRIPTION
+
+swayidle listens for idle activity on your Wayland compositor and executes tasks
+on various idle-related events. You can specify any number of events at the
+command line.
+
+# EVENTS
+
+*timeout* <timeout> <timeout command> [resume <resume command>]
+	Execute _timeout command_ if there is no activity for <timeout> seconds.
+	
+	If you specify "resume <resume command>", _resume command_ will be run when
+	there is activity again.
+
+*before-sleep* <command>
+	If built with systemd support, executes _command_ before systemd puts the
+	computer to sleep.
+
+All commands are executed in a shell.
+
+# EXAMPLE
+
+```
+ swayidle \
+     timeout 300 'swaylock -c 000000' \
+     timeout 600 'swaymsg "output * dpms off"' \
+		resume 'swaymsg "output * dpms on"' \
+     before-sleep 'swaylock -c 000000'
+```
+
+This will lock your screen after 300 seconds of inactivity, then turn off your
+displays after another 600 seconds, and turn your screens back on when resumed.
+It will also lock your screen before your computer goes to sleep.
+
+# AUTHORS
+
+Maintained by Drew DeVault <sir@cmpwn.com>, who is assisted by other open
+source contributors. For more information about sway development, see
+https://github.com/swaywm/sway.
+
+# SEE ALSO
+
+*sway*(5) *swaymsg*(1) *swaygrab*(1) *sway-input*(5) *sway-bar*(5)