docs: improve Doxygen comments.

refs: #1435

Change-Id: I21624ef4eec393c82a50229a07e8277fb6ae4ddf
diff --git a/docs/doxygen.conf.in b/docs/doxygen.conf.in
index c85d71b..2ecc2ad 100644
--- a/docs/doxygen.conf.in
+++ b/docs/doxygen.conf.in
@@ -408,7 +408,7 @@
 # scope will be included in the documentation.
 # The default value is: NO.
 
-EXTRACT_PACKAGE        = NO
+EXTRACT_PACKAGE        = YES
 
 # If the EXTRACT_STATIC tag is set to YES all static members of a file will be
 # included in the documentation.
@@ -2025,7 +2025,7 @@
 # and usage relations if the target is undocumented or is not a class.
 # The default value is: YES.
 
-HIDE_UNDOC_RELATIONS   = YES
+HIDE_UNDOC_RELATIONS   = NO
 
 # If you set the HAVE_DOT tag to YES then doxygen will assume the dot tool is
 # available from the path. This tool is part of Graphviz (see:
@@ -2150,7 +2150,7 @@
 # The default value is: NO.
 # This tag requires that the tag HAVE_DOT is set to YES.
 
-CALL_GRAPH             = NO
+CALL_GRAPH             = YES
 
 # If the CALLER_GRAPH tag is set to YES then doxygen will generate a caller
 # dependency graph for every global function or class method.
@@ -2161,7 +2161,7 @@
 # The default value is: NO.
 # This tag requires that the tag HAVE_DOT is set to YES.
 
-CALLER_GRAPH           = NO
+CALLER_GRAPH           = YES
 
 # If the GRAPHICAL_HIERARCHY tag is set to YES then doxygen will graphical
 # hierarchy of all classes instead of a textual one.