run-tests.py: avoid using popen2.Popen4 - use subprocess instead
Use subprocess to emulate Popen4 if available - similar to how it is done in
util.py.
Using popen2 under python 2.6 gives
DeprecationWarning: The popen2 module is deprecated. Use the subprocess module.
adding a
adding b
adding c
% should succeed
200 Script output follows
/al/
/b/
/c/
200 Script output follows
a
200 Script output follows
b
200 Script output follows
c
% should fail
404 Not Found
error: repository circle not found
404 Not Found
error: repository circle not found
404 Not Found
error: repository circle not found
% collections errors