slaprunner: resiliency: allow jinja to read slapparameter_dict and to bubble intsance parameters to main instance.

1/ FTP doesn't work
2/ ftp://ftp.gmplib.org reads FOR FASTER+SAFER DOWNLOADS USE https.

Obvious effect: don't consider processes like mysql as running if it comes from another partition (case of erp5testnode).
Less obvious effect: don't sync/delete supervisord.sock.
Less obvious effect: in erp5testnode, don't uninstall things from main instace when running buildout of instance of clone runner instance.

A new parameter 'use-nat', True by default will specify if we will setup a nat interface.
if 'use-tap' is Truei (false by default), a tap interface will be connected with a new interface in kvm.
if 'use-tap' and 'use-nat' are True, then virtual machine will have two interfaces, one with tap and
one with nat.

with python 2.6 support that can be still required for initial setup of SlapOS.

even though there are install_requires and setup_requires...