use capture_subprocess instead of capfd. i like the output and behavior much better.
remove more capfd
twiddle pty flags to get rid of \\r problems
capture_subprocess now has a default utf-8 encoding
put pypy, pypy3 back in test
fix pypy: shebangs end with /pypy unless you give --python=python...
remove urwid from "faster" tests.
wheel isn't extraneous
factor out the `combined` capture
we're not ready for venv 2 yet
use threading for tee, eliminate `tee: input/output error` messages
reduce reruns for "faster" tests
Merge pull request #25 from Yelp/no-capfd

No capfd