Update form classes

app/assets/stylesheets/gitlab_bootstrap/forms.scss

app/assets/stylesheets/sections/profile.scss

app/views/admin/broadcast_messages/index.html.haml

app/views/admin/groups/edit.html.haml

app/views/admin/groups/new.html.haml

app/views/admin/hooks/index.html.haml

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

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

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

app/views/groups/_new_group_member.html.haml

app/views/groups/edit.html.haml

app/views/groups/new.html.haml

app/views/profiles/keys/_form.html.haml

app/views/profiles/passwords/edit.html.haml

app/views/profiles/passwords/new.html.haml

app/views/profiles/show.html.haml

app/views/projects/_visibility_level.html.haml

app/views/projects/blob/_remove.html.haml

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

app/views/projects/commits/_image.html.haml