Actual show form errors for profile bio field.
Show signup form errors inline and render non-field form errors as error notifications.

This also makes sure we show the duplicate email error message inline instead of a notification to normalize the error handling between an error with the other email address and one of the Github provided verified email addresses. This is done by demoting the duplicate email form error to a field level error.

Fixes bug #1050008.
Added the correct persona audience to the Django settings as now required by django-allauth.
Merge branch 'master' into github-signup-errors
Moved error messages on signup page between label and form field.
Merge branch 'github-signup-errors' into github-connect-request
Show the validation error for the "other" form field inline instead of on top as a non-field error.
Minor fix to have less spaces.
Combine the username and email notifications code and also show them with form errors.
Show an error message if GitHub username is taken on the first page load.
Improve the "account already exists" form error on submission by adding a link to the Persona-Github workflow.