remove background as the whole colorscheme is updated

vim/vimrc

@@ -41,10 +41,8 @@ endif
 " Themes
 syntax on
 if strftime("%H") > 7 && strftime("%H") < 18
-  set background=light
   colorscheme fruchtig
 else
-  set background=dark
   colorscheme OceanicNext
 end