Uses TeamMembers#index instead, to be more RESTful

We were already calling `authorize_admin_issue!` in a before filter with
the same permission checks, so this deleted check wasn't actually doing
anything.

Handles stuff that's shared across admin controllers.

Also cleans up some alignment and removes unnecessary "to: " arguments

It still works, and it cleans up the output of `rake routes`.

Rename: unicorn.rb.orig --> unicorn.rb.example

Updated development docs

Renamed unicorn.rb.orig to unicorn.rb.example since this seems to be more in line with the common used naming in the config directory. Plus seeing *.orig files I think of the leftovers of git merges, which left me puzzled for quite some time.

Merge branch 'change-notes-order' of https://github.com/riyad/gitlabhq into riyad-change-notes-order