DEV: Rails 5.2 upgrade and global gem upgrade

This updates tests to use latest rails 5 practice
and updates ALL dependencies that could be updated

Performance testing shows that performance has not regressed
if anything it is marginally faster now.

spec/requests/users_email_controller_spec.rb

@@ -6,7 +6,7 @@ describe UsersEmailController do
     it 'errors out for invalid tokens' do
       get "/u/authorize-email/asdfasdf"
 
-      expect(response).to be_success
+      expect(response).to be_successful
       expect(response.body).to include(I18n.t('change_email.already_done'))
     end
 
@@ -21,7 +21,7 @@ describe UsersEmailController do
       it 'confirms with a correct token' do
         get "/u/authorize-email/#{user.email_tokens.last.token}"
 
-        expect(response).to be_success
+        expect(response).to be_successful
 
         body = CGI.unescapeHTML(response.body)
 
@@ -52,7 +52,7 @@ describe UsersEmailController do
           :user_logged_in, :user_first_logged_in
         )
 
-        expect(response).to be_success
+        expect(response).to be_successful
         expect(response.body).to include(I18n.t('change_email.confirmed'))
 
         user.reload
@@ -66,7 +66,7 @@ describe UsersEmailController do
 
         get "/u/authorize-email/#{user.email_tokens.last.token}"
 
-        expect(response).to be_success
+        expect(response).to be_successful
         expect(group.reload.users.include?(user)).to eq(true)
       end
 
@@ -149,7 +149,7 @@ describe UsersEmailController do
               email: other_user.email
             }
 
-            expect(response).to_not be_success
+            expect(response).to_not be_successful
           end
 
           it 'raises an error if there is whitespace too' do
@@ -157,7 +157,7 @@ describe UsersEmailController do
               email: "#{other_user.email} "
             }
 
-            expect(response).to_not be_success
+            expect(response).to_not be_successful
           end
         end
 
@@ -171,7 +171,7 @@ describe UsersEmailController do
               email: other_user.email
             }
 
-            expect(response).to be_success
+            expect(response).to be_successful
           end
         end
       end
@@ -184,7 +184,7 @@ describe UsersEmailController do
             email: other_user.email.upcase
           }
 
-          expect(response).to_not be_success
+          expect(response).to_not be_successful
         end
       end
 
@@ -195,7 +195,7 @@ describe UsersEmailController do
           email: "not_good@mailinator.com"
         }
 
-        expect(response).to_not be_success
+        expect(response).to_not be_successful
       end
 
       it 'raises an error when new email domain is not present in email_domains_whitelist site setting' do
@@ -205,7 +205,7 @@ describe UsersEmailController do
           email: new_email
         }
 
-        expect(response).to_not be_success
+        expect(response).to_not be_successful
       end
 
       context 'success' do