Update the doxygen configuration file.
Minor updates/fixes to the source documentation.
diff --git a/doxygen/tnl.doxy b/doxygen/tnl.doxy
index ce66bd7..c59e861 100644
--- a/doxygen/tnl.doxy
+++ b/doxygen/tnl.doxy
@@ -41,7 +41,7 @@
# Configuration::addtions related to external references
#---------------------------------------------------------------------------
TAGFILES = tnl_dd.tag=../tnl \
- core.tag=../core \
+ main.tag=../core \
math.tag=../math \
swrast.tag=../swrast \
swrast_setup.tag=swrast_setup \