move contribute link further to the top in the book. change URL to /contribute

Author: spier

book/contribute-to-this-book.md book/contribute.mdbook/contribute-to-this-book.md renamed to book/contribute.md

@@ -11,6 +11,7 @@ Instead edit toc_template.md
 # Table of Contents
 
 * [Table of Contents](../book/toc.md)
+* [Contribute to this book](../book/contribute.md)
 
 <img src="./innersource-program-mind-map.png" title="InnerSource Patterns as a Mind Map">
 
@@ -20,7 +21,6 @@ Instead edit toc_template.md
 
 ## Appendix
 
-* [Contribute to this book](../book/contribute-to-this-book.md)
 * [Pattern Template](../meta/pattern-template.md)
 * Extras
   * [README Template](../patterns/2-structured/project-setup/templates/README-template.md)