[session] move context manager logic in the security context manager
The `init_security` and `reset_security` method have no other user that the context manager itself. Having dedicated public function is not useful.
@echo off
rem = """-*-Python-*- script
rem -------------------- DOS section --------------------
rem You could set PYTHONPATH or TK environment variables here
python -x "%~f0" %*
goto exit
"""
# -------------------- Python section --------------------
import sys
from os.path import join, dirname, normpath
sys.path.insert(0, normpath(join(dirname(__file__), '..', '..')))
from cubicweb.cwctl import run
run(sys.argv[1:])
DosExitLabel = """
:exit
rem """