add require for new slide type

otb · otb · commit 215bb6b79354 · 2016-09-21T11:35:00.000-04:00
diff --git a/lib/powerpoint.rb b/lib/powerpoint.rb
@@ -3,6 +3,7 @@
 require 'powerpoint/slide/intro'
 require 'powerpoint/slide/textual'
 require 'powerpoint/slide/pictorial'
+require 'powerpoint/slide/background_picture'
 require 'powerpoint/slide/text_picture_split'
 require 'powerpoint/slide/picture_description'
 require 'powerpoint/compression'
