DOC: increase max number of nodes

Utilities/Doxygen/doxygen.config.in

@@ -2321,7 +2321,7 @@ MSCFILE_DIRS           =
 # Minimum value: 0, maximum value: 10000, default value: 50.
 # This tag requires that the tag HAVE_DOT is set to YES.
 
-DOT_GRAPH_MAX_NODES    = 50
+DOT_GRAPH_MAX_NODES    = 100
 
 # The MAX_DOT_GRAPH_DEPTH tag can be used to set the maximum depth of the graphs
 # generated by dot. A depth value of 3 means that only nodes reachable from the