Admin UI: missing error notifications

You're missing feedback for user on many places. If the error says
'Something went wrong...', it doesn't say much to a user. Even changing
it to denote the current operation would be better, something like
'Unable to create new application'. On most of the $resource.* methods
you're missing the feedback, too. For most of them the information about
success would be annoying, but maybe it could be interesting for user to
see errors like 'Unable to get the application list, check your
connection to the server...'. When my session to the console timed-out,
the operation I was trying to do (renaming of app) didn't do anything,
but I had no clue why.

We need to find places where are notifications missing first.