temp disable failing test_series_stats
add spot-price and wait options; add user-data null option for spark 1.1 compatibility
add readers.py, currently with local fs and boto s3 support
convert images to use reader module for input
better data path normalization in series
add subsample and exportAsPngs to image
fix set creation causing test failure, reenable test
Merge pull request #30 from industrial-sloth/custom-rdds

Custom rdds: s3 reader