more dunderfuture import adds
Adjust teardown in FT runner to take screenshots etc. --ch20l006--
helpers to take screenshot and dump html in base.py. --ch20l007--
get filename for screenshots and dumps. --ch20l008--
add a deliberate test failure to check screenshotting. --ch20l009--
Revert deliberate test failure. --ch20l010--

This reverts commit 2624732383b4351c4bb31625ec1f739b27e6412a.
use wait_for in my lists test around url check. --ch20l012--
wait_for defined in base.py. --ch20l013--
define DEFAULT_WAIT in base. --ch20l014--
deliberately break url check in wait. --ch20l015--
Revert deliberately breaking url check. --ch20l016--

This reverts commit b0446526dcf71b43df192f9d5d89ea2f950b032e.
gitignore screendumps.
add phantom runner.js. --ch20l017--
temporarily break js test. --ch20l019--
Revert temporarily break js test. --ch20l020--

This reverts commit 7eb6cee8529de10af282072a6ae33bc933446440.