Updated tutorial.
Added a function to calculate the intersection between two collections.
Added a function to align 2 dataseries with respect to time
Bug fixed.
Added a helper method to place a market order.
Get the cash without including that from short positions.
Added sample strategy.
Fixed code that downloads CSV files.
Ernie Chan's GLD vs GDX stat arb strategy doc.
Optimized datetime aligned dataseries to avoid recalculating the whole
intersection each time.
Improved testcase.
Bug fixes to statarb_erniechan sample based on feedback from Tibor Kiss.
Improved tutorial.
Updated changelog.
Added VWAP technical indicator.
Added VWAP momentum sample strategy.
Fixed typo.
Removed unused import.
Bug fixed in plotter.py. An IndexError was raised when plotting many dataseries in the same subplot.