doxygen: turn on source browsing

indra/Doxyfile.in

@@ -693,8 +693,7 @@ FILTER_SOURCE_FILES    = NO
 # Note: To get rid of all source code in the generated output, make sure also
 # VERBATIM_HEADERS is set to NO.
 
-## TODO?
-SOURCE_BROWSER         = NO
+SOURCE_BROWSER         = YES
 
 # Setting the INLINE_SOURCES tag to YES will include the body
 # of functions and classes directly in the documentation.
@@ -711,7 +710,7 @@ STRIP_CODE_COMMENTS    = YES
 # then for each documented function all documented
 # functions referencing it will be listed.
 
-REFERENCED_BY_RELATION = NO
+REFERENCED_BY_RELATION = YES
 
 # If the REFERENCES_RELATION tag is set to YES
 # then for each documented function all documented entities
@@ -739,7 +738,7 @@ USE_HTAGS              = NO
 # will generate a verbatim copy of the header file for each class for
 # which an include is specified. Set to NO to disable this.
 
-VERBATIM_HEADERS       = NO
+VERBATIM_HEADERS       = YES
 
 #---------------------------------------------------------------------------
 # configuration options related to the alphabetical class index