Updated the README for generating offline Doxygen docs

doxygen/Makefile

@@ -8,7 +8,6 @@ doc/index.html: build/juce_modules.dox Doxyfile
 	doxygen
 
 build/juce_modules.dox: process_source_files.py $(SOURCE_FILES)
-	rm -rf build
 	python $< ../modules build
 
 clean:

doxygen/README.txt

@@ -1,10 +1,23 @@
-# The JUCE API Reference
+The JUCE API Reference
+======================
 
 From here, you can generate an offline HTML version of the JUCE API Reference.
 
-How to:
+Dependencies
+------------
+
+- doxygen
+- python
+- graphviz (to generate inheritance diagrams)
+
+Make sure that all the dependencies can be found on your PATH.
+
+Building
+--------
+
+- cd into this directory on the command line
+- run `make`
+
+Doxygen will create a new subfolder "doc". Open doc/index.html in your browser
+to access the generated HTML documentation.
 
-1. install doxygen
-2. cd into this directory on the command line
-3. run `make`
-4. doxygen will create a new subfolder "doc" - open doc/index.html in your browser to access the generated HTML documentation

doxygen/make.bat

@@ -0,0 +1,2 @@
+python process_source_files.py ..\modules build
+doxygen

doxygen/process_source_files.py

@@ -75,6 +75,11 @@ if __name__ == "__main__":
                              "subdirectories")
     args = parser.parse_args()
 
+    try: 
+        shutil.rmtree(args.dest_dir)
+    except FileNotFoundError:
+        pass
+
     # Get the list of JUCE modules to include.
     if args.subdirs:
         juce_modules = args.subdirs.split(",")