PEP8 fixes
refactor functions to return DataFrames

- adds to_csv function to output DataFrame with consistent formatting
- all calls to np.savetxt changed to return DataFrames for better
  reusability
Merge pull request #40 from talumbau/df_refactor

Refactor functions into DataFrames
initial commit of taxcalc package

- moved translation.py to taxcalc
- added trivial setup.py for installs
added __init__.py
adding Travis CI script

- tests python 2.7 and 3.4
fixes to .travis.yml
added a requirements.txt for pip
.travis.yml fixes
more .travis.yml fixes
add fake puf2.csv for now
Merge pull request #46 from talumbau/taxcalc_pkg

taxcalc as a package
keeping both versions of SAS code
emulated TJ's package structure
resolved conflicts between accuracy-test and master
removed unnecessary compitem line
refactored and cleaned up main, removed global var
revised compute_error fxn
cleaned up mismatching_records
cleaned up report_accuracy fxn