add wayland specifier to session names (#162)

Create a config option to force ly to add " (Wayland)" to session
names, as long as those names don't already contain the string.

res/config.ini

@@ -83,6 +83,9 @@
 # wayland setup command
 #wayland_cmd = /etc/ly/wsetup.sh
 
+# add wayland specifier to session names
+#wayland_specifier = false
+
 # wayland desktop environments
 #waylandsessions = /usr/share/wayland-sessions