Keyboard.begin(): add Danish and Swedish layouts

Version 1.0.4 of the Keyboard library added the Danish and Swedish
keyboard layouts. Update the documentation of Keyboard.begin()
accordingly.

Author: edgar-bonet

Language/Functions/USB/Keyboard/keyboardBegin.adoc

@@ -33,11 +33,13 @@ When used with a Leonardo or Due board, `Keyboard.begin()` starts emulating a ke
 === Keyboard layouts
 Currently, the library supports the following national keyboard layouts:
 
+* `KeyboardLayout_da_DK`: Denmark
 * `KeyboardLayout_de_DE`: Germany
 * `KeyboardLayout_en_US`: USA
 * `KeyboardLayout_es_ES`: Spain
 * `KeyboardLayout_fr_FR`: France
 * `KeyboardLayout_it_IT`: Italy
+* `KeyboardLayout_sv_SE`: Sweden
 
 
 [float]