add ascending argument for better sorting/Pandas compatibility
PEP8/whitespace fixes (no new functionality)

- lines > 79 chars
- whitespace around operators/commas
- orphaned tabs/spaces
add *.pyc to .gitignore
pass sort to API directly rather than sorting in Python
Merge pull request #3 from jlowin/sort_dates_asc

Sort dates ascending for compatibility with Pandas timeseries conventions, whitespace fixes.