when updating only single items we should not set the
show loading info to true. otherwhise the whole ShowManager
sub components will be reloaded. also it is not true
that the show is loading.

if we want to indicate an ongoing update of the show, we should
introduce a specific flag for that.

While the newly introduced watcher solves the issue when reloading
the dashboard on the ShowManager page, now the show info does not
get loaded when the user logs in on the home pages, waits a few seconds
(in which time all the auth info is already loaded) and then goes to
the ShowManager. In that case the watcher will never trigger after
the creation of the ShowManager.

Now the show info gets loaded right away if the auth info for the
steeringUser is already set.

This is for now hardcoded to 10, but in Aura 1.1 or 1.2 this
should become configurable by the dashboard user.