Merge branch 'more-secure-api' into 'master'

CHANGELOG

app/assets/javascripts/project_users_select.js.coffee

app/assets/javascripts/users_select.js.coffee

app/controllers/application_controller.rb

app/helpers/application_helper.rb

app/models/user.rb

app/services/gravatar_service.rb

doc/api/users.md

lib/api/entities.rb

lib/api/internal.rb

lib/api/projects.rb

lib/api/users.rb

spec/helpers/application_helper_spec.rb

spec/requests/api/notes_spec.rb

spec/requests/api/project_members_spec.rb

spec/requests/api/projects_spec.rb

spec/requests/api/users_spec.rb