The Jetbrains docs clearly state that the only file to .gitignore is workspace.xml. Despite having done this, I keep getting a problem where I lose my configured interpreter when I push from one machine and pull from another. I notice that the project.iml file contains the path to the interpreter like this:
<orderEntry type="jdk" jdkName="Python 3.5.1 (C:\Users\brodiej\AppData\Local\Continuum\Anaconda3\python.exe)" jdkType="Python SDK" />
This path is not the same on my two machines. I'm not sure if this is actually the source of the problem, but it's the best that I've found so far.