fix(docs): put back English PDF

- Removed for debugging and I've forgotten to put it back again

scripts/mkdocs2pdf.py

@@ -247,6 +247,6 @@ def buildDocForLang(lang):
 
 if __name__ == '__main__':
 
-    for l in ['fr']:#, 'en']:
+    for l in ['fr', 'en']:
         print('building PDF doc for language "{}"'.format(l))
         buildDocForLang(l)