[8.0] Port the module 'account_move_template' to the new API

This PR contains the module ***account_move_template*** ported to the new API.
Test and installation seems to me ok.

Let's see what will be the TravisCI response and your reviews :wink: 
Since it is always called on 1 record, you could use `self.ensure_one()` on the top of the method to assert that there is only 1 record, then remove the loop and just use `self` instead of `wizard` everywhere.