Feature request: better registration page

[thhck]

We currently use CSS' default registration page, which is good for advanced user, but not beginner friendly.

Let's create a simpler registration page with:
username
email
password

and assume that :
1 user == 1 pod == 1 webId
webId is stored on the created Pod
username == podname

Also we could add more option, such as:

• profile editing: a form that gather vcard data to fill the profile page at /profile/card
• front page opt-in or opt-out ( see Feature request: opt out from main page #4 )