Add special type inference for http.request proxy object

[trinhanhngoc]

Type of http.request is actually LocalProxy but odoo-stubs fakes it to Request to make PyCharm provide code completion for request's attributes. This leads two problems:

1. Type checking warning:
2. Users who for some reason do not use odoo-stubs will not benefit from code completion.

Since Python does not currently support proxy type hinting, I need to put some magic into the Odoo plugin itself.