Change --show-exc to --show-stderr
Only show stderr when requested.
Fix UnboundLocalError
Merge pull request #128 from mdboom/show-stderr

Change --show-exc to --show-stderr
Add dumb mode to the run command, for quick turnaround
Tweak option string
Handle "existing environments". Work with offline repo.
Fix docs
Fix Python 3
Fix NameError
Fix Conda
Fix Conda
Turn missing Python version back into a warning
Use versions of psutil that are available/compatible with Conda