admin is dead, long live $USER

[Tim Penhey]

Hi folks,

I was thinking that with the upcoming big changes with 2.0, we should
tackle a long held issue where we have the initial user called "admin".

There was a request some time back that we should use the current user's
name. The reason it wasn't implemented at that time was due to logging
into the GUI issues. These have been resolved some time back with the
multiple user support that was added.

All the server side code handles the ability to define the initial user
for the controller model, and we do this in all the tests, so the
default test user is actually called "test-admin".

I *think* that all we need to do is change the default value we use in
the bootstrap command for the AdminUserName (--admin-user flag) from
"admin" to something we derive from the current user.

Probably worth doing now.

Thoughts?

Tim