bake: Add a flag to know which record entries got collapsed from last run. This makes it possible to find entries for things that were actually baked during the current run, as opposed to skipped because they were "clean".

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