On windows, single quote doesn't work as quote character in hook
command line, because "cmd.exe" doesn't recognize it as quoting
character. And this causes failure of test.
This patch uses double quote to quote arguments in hook instead of
single quote for portability.
Even though single quotes for "[hooks] pretxncommit" in
test-clone-pull-corruption.t seems to work correctly (may MinGW sh
treat specially ?) AFAIK, this patch also replaces them by double
quotes for consistency.
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.