Modified to create notebooks folder

documentation/doxygen/Makefile

@@ -7,6 +7,7 @@ export DOXYGEN_SOURCE_DIRECTORY := ../..
 export DOXYGEN_ROOT_VERSION := $(shell root -l -b -q -e 'printf("%s\n", gROOT->GetVersion());')
 export DOXYGEN_EXAMPLE_PATH := $(DOXYGEN_OUTPUT_DIRECTORY)/macros
 export DOXYGEN_IMAGE_PATH := $(DOXYGEN_OUTPUT_DIRECTORY)/html
+export DOXYGEN_NOTEBOOK_PATH := $(DOXYGEN_OUTPUT_DIRECTORY)/notebooks
 export DOXYGEN_STRIP_PATH := $(shell cd $(PWD)/../..; pwd)
 export DOXYGEN_INCLUDE_PATH := $(shell find $(DOXYGEN_STRIP_PATH) -type d -name dictpch -prune -o -type d -name inc)
 
@@ -20,6 +21,7 @@ folders:
 	if [ ! -d $(DOXYGEN_EXAMPLE_PATH) ]; then mkdir $(DOXYGEN_EXAMPLE_PATH); fi
 	if [ ! -d $(DOXYGEN_MATHJAX_PATH) ]; then mkdir $(DOXYGEN_MATHJAX_PATH); fi
 	if [ ! -d $(DOXYGEN_IMAGE_PATH) ]; then mkdir $(DOXYGEN_IMAGE_PATH); fi
+	if [ ! -d $(DOXYGEN_NOTEBOOK_PATH) ]; then mkdir $(DOXYGEN_NOTEBOOK_PATH); fi
 
 mathjax:
 	tar xfz mathjax.tar.gz -C $(DOXYGEN_OUTPUT_DIRECTORY)/html