Updated rspec to rspec 3.x syntax

bin/rspec

spec/controllers/application_controller_spec.rb

spec/controllers/blob_controller_spec.rb

spec/controllers/branches_controller_spec.rb

spec/controllers/commit_controller_spec.rb

spec/controllers/commits_controller_spec.rb

spec/controllers/import/github_controller_spec.rb

spec/controllers/import/gitlab_controller_spec.rb

spec/controllers/merge_requests_controller_spec.rb

spec/controllers/projects_controller_spec.rb

spec/controllers/tree_controller_spec.rb

spec/factories_spec.rb

spec/features/admin/admin_hooks_spec.rb

spec/features/admin/admin_projects_spec.rb

spec/features/admin/admin_users_spec.rb

spec/features/admin/security_spec.rb

spec/features/atom/dashboard_issues_spec.rb

spec/features/atom/dashboard_spec.rb

spec/features/atom/issues_spec.rb

spec/features/atom/users_spec.rb