Developer Guide: Add missing heading.

diff --git a/developerGuide.t2t b/developerGuide.t2t
index 06df5ac..86534b5 100644 (file)
--- a/developerGuide.t2t
+++ b/developerGuide.t2t
@@ -140,6 +140,7 @@ They are able to:
 - Customise or add new support for text content and complex documents.\r
 -\r
 \r
++ Plugins +\r
 This section provides an introduction to developing plugins.\r
 Developers should consult the code documentation for a complete reference.\r
 \r