documentation: Add various tags and fix section order.

Previously, the `Signals` section was shown before the `Functions`.
This was confusing and different from other framework documentation.

It partially work. Not all ldoc output display the functions at the
top, but some does. Previously, none did.

This commit also add 3 new sections:

 * property: For object properties, replacing the "fields" table
   from the current documentations.
 * deprecated: For deprecated methods
 * beautiful: For widgets theme options

docs/config.ld

@@ -28,8 +28,19 @@ tparam_alias('client', 'client.object')
 tparam_alias('tag', 'tag')
 -- Should be default, but is not.  Sets up "@tab" => "@tparam table".
 tparam_alias('tab', 'table')
+
+-- Hack to get the functions and method on top of the signals and properties
+new_type("function", "Functions")
+-- Documentation for objects properties
+new_type("property", "Object properties", false, "Type")
 -- New type for signals
 new_type("signal", "Signals", false, "Arguments")
+-- Allow objects to define a set of beautiful properties affecting them
+new_type("beautiful", "Theme variables", false, "Type")
+-- Put deprecated methods in their own section
+new_type("deprecated", "Deprecated functions", false, "param")
+-- For the legacy stateless layout related functions
+new_type("legacylayout", "Layout related functions", false, "param")
 
 -- More fitting section names
 kind_names={topic='Documentation', module='Libraries'}