Fix doxygen build

Author: cardigliano

doc/Makefile.in

@@ -52,8 +52,15 @@ help:
 clean:
 	rm -rf $(BUILDDIR)/*
 
+.PHONY: doxygen
+doxygen:
+	cd doxygen && doxygen Doxyfile
+
+doxygen/xml/index.xml:
+	$(MAKE) doxygen
+
 .PHONY: html
-html:
+html: doxygen/xml/index.xml
 	$(SPHINXBUILD) -b html $(ALLSPHINXOPTS) $(BUILDDIR)/html
 	@echo
 	@echo "Build finished. The HTML pages are in $(BUILDDIR)/html."

doc/conf.py.in

@@ -25,8 +25,7 @@ extensions = [
     'breathe'
 ]
 
-# Commented temporarely
-#breathe_projects = { "apidoc" : "doxygen/xml/" }
+breathe_projects = { "apidoc" : "doxygen/xml/" }
 
 breathe_default_project = "apidoc"