Merge branch 'release/0.11.2'
Add requirements.txt to MANIFEST.in
Add a little documentation to web.py
Ensure that memory and CPU values are floats
Make fetch_input count as a heartbeat, and ensure that functions that return None on purpose work.
Add some more debug output to test_gridmap.py
Fix issue where exceptions where unpickling exceptions were not being stored properly
Merge branch 'master' into develop