Many tests didn't change back from subdirectories at the end of the tests ...
and they don't have to. The missing 'cd ..' could always be added when another
test case is added to the test file.
This change do that tests (99.5%) consistently end up in $TESTDIR where they
started, thus making it simpler to extend them or move them around.
Currently we have the following return codes if nothing is found:
commit incoming outgoing pull push
intended 1 1 1 1 1
documented 1 1 1 0 1
actual 1 1 1 0 1
This makes pull agree with the rest of the table and makes it easy to
detect "nothing was pulled" in scripts.