avatar upload on profile page

CHANGELOG

app/assets/javascripts/profile.js.coffee

app/assets/javascripts/users_select.js.coffee

app/helpers/application_helper.rb

app/helpers/commits_helper.rb

app/helpers/projects_helper.rb

app/models/user.rb

app/views/admin/users/show.html.haml

app/views/dashboard/issues.atom.builder

app/views/dashboard/show.atom.builder

app/views/events/_event.html.haml

app/views/groups/issues.atom.builder

app/views/groups/show.atom.builder

app/views/layouts/_head_panel.html.haml

app/views/profiles/show.html.haml

app/views/projects/branches/_branch.html.haml

app/views/projects/commits/show.atom.builder

app/views/projects/issues/_issues.html.haml

app/views/projects/issues/index.atom.builder

app/views/projects/merge_requests/index.html.haml