[web] Add missing import of _DATA_DIR in webctl
Followup on d84bc85f7f70 which introduced usage of this name in
_datadirs method of GenStaticDataDirMixIn but resulted into a NameError
at runtime and makes migrations crash.
--- a/cubicweb/web/webctl.py Thu Feb 15 11:04:20 2018 +0100
+++ b/cubicweb/web/webctl.py Thu Mar 22 10:04:54 2018 +0100
@@ -31,6 +31,7 @@
from cubicweb.cwctl import CWCTL
from cubicweb.cwconfig import CubicWebConfiguration as cwcfg
from cubicweb.toolsutils import Command, CommandHandler, underline_title
+from cubicweb.web.webconfig import _DATA_DIR
try: