Move `api/v3/deployments` to the correct namespace

lib/api/deployments.rb

 module API
-  # Deployments RESTfull API endpoints
+  # Deployments RESTful API endpoints
   class Deployments < Grape::API
     include PaginationParams
 

lib/api/v3/deployments.rb

 module API
-  # Deployments RESTfull API endpoints
-  class Deployments < Grape::API
-    include PaginationParams
+  module V3
+    # Deployments RESTful API endpoints
+    class Deployments < Grape::API
+      include PaginationParams
 
-    before { authenticate! }
+      before { authenticate! }
 
-    params do
-      requires :id, type: String, desc: 'The project ID'
-    end
-    resource :projects do
-      desc 'Get all deployments of the project' do
-        detail 'This feature was introduced in GitLab 8.11.'
-        success ::API::V3::Deployments
-      end
       params do
-        use :pagination
+        requires :id, type: String, desc: 'The project ID'
       end
-      get ':id/deployments' do
-        authorize! :read_deployment, user_project
+      resource :projects do
+        desc 'Get all deployments of the project' do
+          detail 'This feature was introduced in GitLab 8.11.'
+          success ::API::V3::Deployments
+        end
+        params do
+          use :pagination
+        end
+        get ':id/deployments' do
+          authorize! :read_deployment, user_project
 
-        present paginate(user_project.deployments), with: ::API::V3::Deployments
-      end
+          present paginate(user_project.deployments), with: ::API::V3::Deployments
+        end
 
-      desc 'Gets a specific deployment' do
-        detail 'This feature was introduced in GitLab 8.11.'
-        success ::API::V3::Deployments
-      end
-      params do
-        requires :deployment_id, type: Integer,  desc: 'The deployment ID'
-      end
-      get ':id/deployments/:deployment_id' do
-        authorize! :read_deployment, user_project
+        desc 'Gets a specific deployment' do
+          detail 'This feature was introduced in GitLab 8.11.'
+          success ::API::V3::Deployments
+        end
+        params do
+          requires :deployment_id, type: Integer,  desc: 'The deployment ID'
+        end
+        get ':id/deployments/:deployment_id' do
+          authorize! :read_deployment, user_project
 
-        deployment = user_project.deployments.find(params[:deployment_id])
+          deployment = user_project.deployments.find(params[:deployment_id])
 
-        present deployment, with: ::API::V3::Deployments
+          present deployment, with: ::API::V3::Deployments
+        end
       end
     end
   end