Via installing Products.signalstack

    https://pypi.python.org/pypi/Products.signalstack

/reviewed-by @Tyagov

Conflicts:
	software/kvm/common.cfg
	software/wendelin/software.cfg

Redirect in nginx does not behave the same depending on wether it is
accessed directly or behind apache proxy.

- name wrapper bash, not sh as bash behave like sh when named sh
- add -l so that bash runs as login shell and reads .bash_profile
- enable colors in profile
- output a message in profile
- remaining TODOs: a working slapos node command

This required slapos.toolbox 0.50

If no htpasswd file exist, redirect to account creation page

This should not depend on the environment when executing slapos node
instance

Since shellinabox listen on AF_UNIX, we don't need another password for
shellinabox