vcs-imports cannot post +sourceadmin

[David Allouche]

I need admin membership to be able to post the +sourceadmin form. This form should be usable by members of the vcs-imports team.

[David Allouche (ddaa)]

To test that, you should create a new person in the sampledata that has no permission except membership of the vcs-imports team.

That person will be useful in testing other interesting permission issues involving vcs imports.