Update travis-core, which fixes PUT /hooks/:id

Gemfile.lock

@@ -42,7 +42,7 @@ GIT
 
 GIT
   remote: git://github.com/travis-ci/travis-core.git
-  revision: cb999efb7015007423d75df412f076f26d35b09d
+  revision: 23c0c1b07f34033e598f02bfd03ec99b01198fce
   specs:
     travis-core (0.0.1)
       actionmailer (~> 3.2.3)

spec/integration/v2/hooks_spec.rb

@@ -37,8 +37,9 @@ describe 'Hooks' do
     it 'sets the hook' do
       GH.stubs(:[]).returns([])
       GH.expects(:post).with(target, payload).returns(GH.load(PAYLOADS[:github][:hook_active]))
-      put 'hooks', { hook: { id: hook.id, active: 'true' } }, headers
+      response = put 'hooks', { hook: { id: hook.id, active: 'true' } }, headers
       repo.reload.active?.should be_true
+      response.should be_successful
     end
   end
 end