Tweak URI documentation as a result of discussion with Sebastian and Sam

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpclient/trunk@818594 13f79535-47bb-0310-9956-ffa450edef68

httpclient/src/main/java/org/apache/http/client/methods/HttpRequestBase.java

@@ -74,6 +74,12 @@ public abstract class HttpRequestBase extends AbstractHttpMessage
         return HttpProtocolParams.getVersion(getParams());
     }
 
+    /**
+     * Returns the original request URI. 
+     * <p>
+     * Please note URI remains unchanged in the course of request execution and 
+     * is not updated if the request is redirected to another location.
+     */
     public URI getURI() {
         return this.uri;
     }