Bind to a control socket

So far using a lockfile, which kind of sucks.

We're going to connect to DBus directly, so we'll see
if it can't be used for our purposes in a simple way.

meson.build

@@ -16,10 +16,14 @@ dependencies = [
 	dependency('gtk+-3.0'),
 	dependency('gmodule-2.0'),
 	dependency('gio-2.0'),
+	dependency('gio-unix-2.0'),
 	dependency('gee-0.8'),
 	dependency('sqlite3'),
 	dependency('x11'),
 
+	# Only because of flock
+	meson.get_compiler('vala').find_library('posix'),
+
 	# Ours
 	dependency('xext'),
 	dependency('xextproto'),