Pyramid-simpleauth

Restrict the set of permissions granted to `self.user` in owned acl mixins.
Add a `PersonalMixin` for content other users shouldn't see.

Stop forcing passwords to lower case. Note that this is a fairly major
api change and means that existing user accounts may need to login with
lower case passwords where before they were using upper case.

Limit `/auth/logout` to POST requests.

Provide account management features (thanks to amarandon):

* change password
* change username
* manage email accounts

Updated form.mako to follow new bootstrap syntax.

Added `request.is_post_login` and `request.is_post_signup`.

Add `request.user_json` property.