catch stdout thrown on assert raises for strictio

[mmckerns]

From #57, In test/test_file.py, when strictio=True, stdout is generated -- roughly corresponding to each of the assert using throws. This should be trapped. Further, if stdout is thrown from dill (but not errors) in these cases, that should also be trapped.

[mmckerns]

disabled strictio in 1fa9cef. Leaving this open, as bug is still present when strictio is enabled.

[mmckerns]

may be able to shunt error to another subprocess

[matsjoyce]

Another option that I've used before is unittest.TextTestRunner(verbosity=2, buffer=True).run(tests), which only displays output if the corresponding test fails. That would need to wait for #3, though.

[mmckerns]

good point.

BTW: I've disabled strictio only very temporarily… soon as the release is out, I'll enable it again but with this error handled.