[FIX] 1.2 compatibility

app.add_node doesn't work right for custom translators in 1.2, since
mementos are using ``h:div`` reimplement that in the
BootstrapTranslator.

Alternative would be to monkeypatch app.add_node for Sphinx 1.2, but
let's not do that...

_extensions/odoo/__init__.py

@@ -8,7 +8,10 @@ import sphinx.environment
 import sphinx.builders.html
 from docutils import nodes
 def setup(app):
-    app.set_translator('html', translator.BootstrapTranslator)
+    if getattr(app.config, 'html_translator_class', None):
+        app.warn("Overriding the explicitly set  html_translator_class setting",
+                 location="odoo extension")
+    app.config.html_translator_class = 'odoo.translator.BootstrapTranslator'
 
     switcher.setup(app)
     app.add_config_value('odoo_cover_default', None, 'env')