refactor: URL cleanup for recently migrated content

Relates to eclipsefdn/it/websites/eclipse.org#601

CONTRIBUTING.md

@@ -18,7 +18,7 @@ The project maintains the following source code repositories
 Before your contribution can be accepted by the project team contributors must
 electronically sign the Eclipse Contributor Agreement (ECA).
 
-* http://www.eclipse.org/legal/ECA.php
+* http://www.eclipse.org/legal/eca/
 
 Commits that are provided by non-committers must have a Signed-off-by field in
 the footer indicating that the author is aware of the terms by which the

src/main/resources/templates/pages/error.html

@@ -4,8 +4,8 @@
   <ul>
     <li><a href="//eclipse.org">Eclipse home</a></li>
     <li><a href="//eclipse.org/projects/searchpage.php">Search</a> our site</li>
-    <li>Website <a href="//eclipse.org/legal/privacy.php">privacy policy</a> and <a href="//eclipse.org/legal/termsofuse.php">terms of use</a></li>
-    <li><a href="//eclipse.org/legal">Legal documents</a></li>
+    <li>Website <a href="//eclipse.org/legal/privacy/">privacy policy</a> and <a href="//eclipse.org/legal/terms-of-use/">terms of use</a></li>
+    <li><a href="//eclipse.org/legal/">Legal documents</a></li>
     <li><a href="//eclipse.org/artwork/">Logos</a> and artwork</li>
     <li><a href="//wiki.eclipse.org/index.php/Webmaster_FAQ">webmaster FAQ</a></li>
     <li><a href="mailto:webmaster@eclipse.org">Email the webmaster</a></li>