INT-1639 Externalize SpEL Evaluation Context

Allow modification of context property accessors and
functions.

Polishing

- Fix tests to ensure the EvaluationContextFactoryBean is
available when necessary.

Polishing - Use Utility for ALL EvaluationContexts

Add Test Showing Custom Function

See SpelTransformerIntegrationTests-context.xml

Polishing

Polishing -fix Remote Sync

Polishing - Emit WARN if No BeanFactory

Polishing - Do Not Override ConversionService

Kludge to Prevent Warning When No BeanFactory

Expressions for method invoking in the MessagingMethodInvokerHelper
don't need a BeanFactory - suppress the warning.

Polishing - PR Comments - Invert Boolean

spring-integration-mail/src/test/java/org/springframework/integration/mail/config/InboundChannelAdapterParserTests.java

@@ -28,6 +28,8 @@ import javax.mail.Authenticator;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
+import org.xml.sax.SAXParseException;
+
 import org.springframework.beans.DirectFieldAccessor;
 import org.springframework.beans.factory.BeanCreationException;
 import org.springframework.beans.factory.BeanDefinitionStoreException;
@@ -45,7 +47,6 @@ import org.springframework.integration.mail.SearchTermStrategy;
 import org.springframework.integration.test.util.TestUtils;
 import org.springframework.test.context.ContextConfiguration;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
-import org.xml.sax.SAXParseException;
 
 /**
  * @author Mark Fisher
@@ -132,6 +133,7 @@ public class InboundChannelAdapterParserTests {
 		assertEquals(ImapMailReceiver.class, receiver.getClass());
 		Boolean value = (Boolean) new DirectFieldAccessor(receiver).getPropertyValue("shouldDeleteMessages");
 		assertTrue(value);
+		assertNotNull(TestUtils.getPropertyValue(receiver, "evaluationContext.beanResolver"));
 	}
 
 	@Test