Add some more Lua script examples

scripts/_session_load_hook.lua

@@ -0,0 +1,32 @@
+ardour {
+	["type"]    = "EditorHook",
+	name        = "Load Session Hook Example",
+	author      = "Ardour Lua Task Force",
+	description = "Display some dialogs during session load and execute actions",
+}
+
+-- subscribe to signals
+-- http://manual.ardour.org/lua-scripting/class_reference/#LuaSignal.LuaSignal
+function signals ()
+	s = LuaSignal.Set()
+	s:add ({[LuaSignal.SetSession] = true})
+	return s
+end
+
+-- create callback functions
+function factory () return function (signal, ...)
+	assert (signal == LuaSignal.SetSession)
+	local md = LuaDialog.Message ("Set Session", "Loading Session:" .. Session:name(), LuaDialog.MessageType.Info, LuaDialog.ButtonType.Close)
+	md:run()
+
+	local dialog_options = {
+		{ type = "checkbox", key = "tempo", default = true, title = "Show Tempo Ruler" },
+		{ type = "checkbox", key = "meter", default = true, title = "Show Meter Ruler" },
+	}
+	local dlg = LuaDialog.Dialog ("Tweak Rulers", dialog_options)
+	local rv = dlg:run()
+	if (rv) then
+		Editor:set_toggleaction ("Rulers", "toggle-tempo-ruler",  rv['tempo'])
+		Editor:set_toggleaction ("Rulers", "toggle-meter-ruler",  rv['meter'])
+	end
+end end