Add Python Support

[Mytherin]

This PR adds Python support in the miniparquet module. Currently the module has a single function miniparquet.read(filename) that reads a miniparquet file and converts it into a dictionary of lists.

Several open issues still:

• Dates need to be converted (need to do some magic to convert epoch to sec/minute/hour/day/month/year)
• Should probably convert to NumPy arrays or pandas, not to Python lists
• Need to add tests

But then I only had 45 minutes to implement it :)

Usage:

import miniparquet

print(miniparquet.read('tests/data/alltypes_plain.parquet'))