Fix broken link to overview

src/docs/asciidoc/index.adoc

@@ -4,7 +4,7 @@
 
 Welcome to the Spring Framework reference documentation!
 
-Please read the <<overview.adoc,*Overview*>> for a quick introduction including brief history,
+Please read the <<overview.adoc#overview,*Overview*>> for a quick introduction including brief history,
 design philosophy, where to ask questions, and tips to get started. For information on
 "What's New", or "Migrating from previous versions", check the
 https://github.com/spring-projects/spring-framework/wiki[*Github Wiki*].

src/docs/asciidoc/overview.adoc

@@ -2,6 +2,7 @@
 :toclevels: 1
 :docinfo1:
 
+[[overview]]
 = Spring Framework Overview
 
 Spring makes it easy to create Java enterprise applications. It provides everything you