po4a: add the space cleaning option

scripts/create_po4a_conf

@@ -6,7 +6,7 @@ with open('po4a.conf', 'w') as f:
     langs = [ l[17:-3] for l in glob.glob('po/documentation.*.po')]
     langs.sort()
     f.write(' '.join(langs))
-    f.write('\n[po4a_paths] po/documentation.pot $lang:po/documentation.$lang.po\n[options] opt: " -k 80"\n')
+    f.write('\n[po4a_paths] po/documentation.pot $lang:po/documentation.$lang.po\n[options] opt: " -k 80 -o cleanspaces=1"\n')
     with open('sources.txt', 'r') as sources:
         for source in sources:
             source = source.strip()