XD-1251 Allow config of Access-Control-Allow-Origin

Use can set the value xd.ui.allow_origin to override the
default (http://localhost:9889).
XD-804 Added integration.support package to dirt and used in AbstractSingleNode...Tests
XD-804 fixed a bug in AbstractSingleNodeNamedChannelSink
XD-804 Split integration.support package into source and sink
XD 804 renamed methods in SingleNodeIntegratonSupport
XD-804 added ExampleProcessingChainTests
XD-804 fixed bug in SingleNodeIntegrationSupport
XD-804 refactored and enhanced SingleNodeProcessingChain
XD-804 Merged SingleNodeIntegrationSupport into SingleNodeApplication