Remove beds/Changelog.txt & farming/API.txt

- beds/Changelog.txt probably won't be updated because http://dev.minetest.net/Changelog is used instead
- The information in farming/API.txt is already documented in game_api.txt

mods/beds/Changelog.txt

@@ -1,18 +0,0 @@
-1.0.1 beta
-----------
-- Add backwards compatibility with PilzAdam's beds mod
-- Fix placement
-- Fix small bugs
-- Prevent possible crash
-
-1.1
----
-- Add fancy bed model (based on jp's model)
-- Add API to register beds
-- Allow players always to detach from bed (by donat-b) 
-- If more than 50% of players want sleep they can skip the night
-- Don't show sleep dialog in singleplayer
-
-1.1.1
------
-- Prevent possbile crash by trying to reposition leaving players