Added metadata fields to scripts that script_manager can access and

display as a tooltip.

Added script_manager integration to those scripts that didn't have it.

contrib/slideshowMusic.lua

@@ -31,21 +31,28 @@ local gettext = dt.gettext.gettext
 
 du.check_min_api_version("7.0.0", "slideshowMusic") 
 
+dt.gettext.bindtextdomain("slideshowMusic", dt.configuration.config_dir .."/lua/locale/")
+
+local function _(msgid)
+    return gettext(msgid)
+end
+
 -- return data structure for script_manager
 
 local script_data = {}
 
+script_data.metadata = {
+  name = "slideshowMusic",
+  purpose = _("play music during a slideshow"),
+  author = "Tobias Jakobs",
+  help = "https://docs.darktable.org/lua/stable/lua.scripts.manual/scripts/contrib/slideshowMusic"
+}
+
 script_data.destroy = nil -- function to destory the script
 script_data.destroy_method = nil -- set to hide for libs since we can't destroy them commpletely yet, otherwise leave as nil
 script_data.restart = nil -- how to restart the (lib) script after it's been hidden - i.e. make it visible again
 script_data.show = nil -- only required for libs since the destroy_method only hides them
 
-gettext.bindtextdomain("slideshowMusic", dt.configuration.config_dir .."/lua/locale/")
-
-local function _(msgid)
-    return gettext(msgid)
-end
-
 local function playSlideshowMusic(_, old_view, new_view)
   local filename, playMusic