TracPy

This is the first official release of TracPy. Many options are currently working in the code:

• 2D tracking has been most thoroughly tested
• 3D should run, but has not been tested too much
• Sub grid diffusion types work, though doturb=3 is the least tested of the three
• the user manual, an iPython notebook in /docs, should be working well
• the tests should all run properly