s4-python: python is not always in /usr/bin

Using "#!/usr/bin/env python" is more portable. It still isn't ideal
though, as we should really use the python path found at configure
time. We do that in many places already, but some don't.

Signed-off-by: Andrew Bartlett <abartlet@samba.org>

source4/scripting/python/samba/netcmd/dsacl.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 #
 # Manipulate ACLs on directory objects
 #