RTD to build doxygen xml before using Sphinx

docs/sphinx/conf.py

@@ -21,7 +21,7 @@ import subprocess, os
 read_the_docs_build = os.environ.get('READTHEDOCS', None) == 'True'
 
 if read_the_docs_build:
-
+    print('Running on read the docs')
     subprocess.call('cd ../doxygen; make', shell=True)