GH-293 Enhanced endpoint mapping support for functional form context configuration

- Enhanced HTTP endpoint mapping support for 'functional form' context configuration ensuring it can register multiple endpoint to maintain the same behaviour as with regular application context
- Additional consolidation around Function Catalog
- Added identical test for functional and non-functional form endpoint configuration.

Resolves #293

spring-cloud-function-context/src/test/java/org/springframework/cloud/function/context/catalog/InMemoryFunctionCatalogTests.java

@@ -44,7 +44,7 @@ public class InMemoryFunctionCatalogTests {
 		InMemoryFunctionCatalog catalog = new InMemoryFunctionCatalog();
 		catalog.register(registration);
 		FunctionRegistration<?> registration2 = catalog.getRegistration(function);
-		assertThat(registration2).isSameAs(registration);
+		assertThat(registration2.getType()).isEqualTo(registration.getType());
 	}
 
 	@Test

spring-cloud-function-context/src/test/java/org/springframework/cloud/function/context/config/ContextFunctionCatalogInitializerTests.java

@@ -50,7 +50,7 @@ import static org.assertj.core.api.Assertions.assertThat;
 
 /**
  * @author Dave Syer
- *
+ * @author Oleg Zhurakousky
  */
 public class ContextFunctionCatalogInitializerTests {
 
@@ -163,7 +163,7 @@ public class ContextFunctionCatalogInitializerTests {
 		assertThat(bean).isNotSameAs(function);
 		assertThat(this.inspector.getRegistration(function)).isNotNull();
 		assertThat(this.inspector.getRegistration(function).getType()).isEqualTo(
-				FunctionType.from(String.class).to(String.class).wrap(Flux.class));
+				FunctionType.from(String.class).to(String.class));
 	}
 
 	@Test