bug: Fix copying of page assets during the bake. * The `Assetor` wasn't setting the "used assets" flag on the correct object. (I wonder why Python didn't complain about that) * The baker wasn't looking at the right input filename.

sudo: false
language: python
python:
  - "3.4"
install:
  - "pip install -r requirements.txt"
  - "pip install -r dev-requirements.txt"
script: py.test