Set a default value for arguments of cubicweb.cwctl:run()

This will help making a console script entry point from this to get rid
of the custom installation of scripts in setup.py.

Accordingly, update all calls of this function.

bin/cubicweb-ctl

 #!/usr/bin/env python
 from cubicweb.cwctl import run
-import sys
-run(sys.argv[1:])
+run()

cubicweb/__main__.py

 from cubicweb.cwctl import run
-import sys
 
-run(sys.argv[1:])
+run()

cubicweb/cwctl.py

@@ -1078,7 +1078,7 @@ for cmdcls in (ListCommand,
 
 
 
-def run(args):
+def run(args=sys.argv[1:]):
     """command line tool"""
     import os
     filterwarnings('default', category=DeprecationWarning)
@@ -1093,4 +1093,4 @@ def run(args):
         sys.exit(2)
 
 if __name__ == '__main__':
-    run(sys.argv[1:])
+    run()