Fix HTTP urls to HTTPS

* Do not fix urls for the `http://apache.org/xml/features` when we
configure XML components
* Do not fix urls for localhost and fake links in tests
* Fix all the dead links in docs

spring-integration-http/src/main/java/org/springframework/integration/http/dsl/HttpInboundEndpointSupportSpec.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2018 the original author or authors.
+ * Copyright 2017-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -364,7 +364,7 @@ public abstract class HttpInboundEndpointSupportSpec<S extends HttpInboundEndpoi
 		}
 
 		/**
-		 * List of allowed origins, e.g. {@code "http://domain1.com"}.
+		 * List of allowed origins, e.g. {@code "https://domain1.com"}.
 		 * <p>These values are placed in the {@code Access-Control-Allow-Origin}
 		 * header of both the pre-flight response and the actual response.
 		 * {@code "*"} means that all origins are allowed.

spring-integration-http/src/main/resources/org/springframework/integration/http/config/spring-integration-http-5.2.xsd

@@ -8,7 +8,7 @@
 	<xsd:import namespace="http://www.springframework.org/schema/beans" />
 	<xsd:import namespace="http://www.springframework.org/schema/tool" />
 	<xsd:import namespace="http://www.springframework.org/schema/integration"
-				schemaLocation="http://www.springframework.org/schema/integration/spring-integration-5.2.xsd" />
+				schemaLocation="https://www.springframework.org/schema/integration/spring-integration-5.2.xsd" />
 
 	<xsd:annotation>
 		<xsd:documentation><![CDATA[