Improvements in TALES tests and Interfaces display

[glenfant]

- Provide same variables as in portal_actions in TALES tests
  [glenfant]

- Emphasize marker interfaces with an (ugly) "(*)" prefix.

Note that the new comments for TALES test in template will break one translation label.

@glenfant @vangheem I'm getting an error here:

"""File "/home/thet-data/data/dev/cloud19/wireframe/noeku-buildout/src/plone.app.debugtoolbar/src/plone/app/debugtoolbar/browser/context.py", line 118, in update
    secu_label = 'Roles: ' + ', '.join([r for r in secu_infos[:-1]])
TypeError: sequence index must be integer, not 'slice'
"""
the secu_infos object is the following:
```
(Pdb) secu_infos
<imPermissionRole object at 0x7fd16559f5b0>
(Pdb) secu_infos.__class__
<type 'imPermissionRole'>
(Pdb) secu_infos.__doc__
'imPermissionRole C implementation'
```

as you can see above, i'm using the ``C`` security mplementation. normally in development environments, we use the python security implementation with ``verbose-security on`` set for ``plone.recipe.zope2instance``. maybe this error doesn't occur for the Python security implementation.

anyways, this should be fixed!

@glenfant please annotate your code a bit more with some comments. it's not obvious, what it does, especially where you do all the list slicing.