New user Registration, Confirmation and session management workflow

[danguita]

Connects to #126.

What does this PR do?

This PR implements the latest specs regarding User registration and session management. In brief, it adds a new Registration and Confirmation workflow, which can be accessed right from the login screen. This updated UI is also providing a way for requesting a password change.

It is also localising and translating any related template by keeping conventions established in the GobiertoAdmin module.

What is missing?

Once again, I'd need some help with CA translations. I'm keeping them mirrored from ES versions to leave a placeholder to work with 🙏

How should this be manually tested?

Just get into the new login screen at http:https://madrid.gobierto.dev/user/login, and check that:

• Any User can recover her password.
• Any Visitor can register in the new workflow: 1. Ask for email, 2. Ask for the remaining data.
• Any User can start a session with valid credentials.
• Every interaction is localised and translated into the current locale (please note the CA translations are not done yet).
• The UI looks and behaves like the prototype.

Here're a couple of shots on those:

[ferblape]

I have made a few changes:

1 - include missing Catalan translations, so now the feature is complete
2 - remove duplicated login routes
3 - fix the name of the gender attribute, because when there were validation errors, it wasn't very clear which attribute it was
4 - sorted and updated the years of the year of birth selector

[ferblape]

BTW, great job!

[danguita]

I do need more sleep 😞

[danguita]

Thanks for taking care, go ahead! 👍