Work on 03_fip.py

Continuing the translation from R script to python
Merge pull request #199 from benjello/dev

Fixing erf datatable
Continued work on 03_fip.py
Merge branch 'dev' of https://github.com/openfisca/openfisca into dev

Conflicts:
	src/countries/france/data/erf/datatable.py
Merge pull request #200 from jsantoul/dev

Continued work on 03_fip.py
erf still work in progress
Resolving merge conflicts