More authentication policy fixes after switch to login
This contains the remaining fixes around authentication policy after the introduction of ERP5 Login.
Here I am changed API so that login_account_provide's analyzePassword directly returns the messages instances and not error code, this way we can easily use analyzePassword to check passwords in various password fields validator.
You may think "why don't we use the same script for all validators ?", the answer is that depending on the context, the logic to find the login for which we want to check the password is different ( when "changing own password", it is the currently logged in user, in portal password password reset it is as we dicussed in !185 (comment 19760) , in new user creation dialog it would also be different), so it makes sense to have different validator scripts all reusing analyzePassword .
This was applied to Password tool to fix #20161021-F85D7 and also to Preference's tool "change own password" dialog.
There are other small fixes.