Use dash hack for PyPy+IPython

Fixes #1051
Closes #919 (I hope so)
Modify postproc to make pypy tests work

Note: modification to test.sh is there because if running test outside of 
a virtualenv postproc.py will behave incorrectly.
Merge pull request #1202 from ZyX-I/fix-1051

Use dash hack for PyPy+IPython