qiworktree: we need depth=4 for multi-configuration jobs on hudson
qiworktree: we need depth=4 for multi-configuration jobs on hudson

Revert this if it gets too slow
(Better yet, use a "filesystem cache" ala waf)

dmerejkowsky/qibuild,aldebaran/qibuild,dmerejkowsky/qibuild,aldebaran/qibuild,aldebaran/qibuild,dmerejkowsky/qibuild,dmerejkowsky/qibuild,dmerejkowsky/qibuild,aldebaran/qibuild