Add password reset request handling to the account page

As per [ECOM-347](https://openedx.atlassian.net/browse/ECOM-347). The next step in the password reset process (confirmation) is currently handled by student.views.password_reset_confirm_wrapper, a custom wrapper around Django's password reset confirmation view.

@wedaly and @stephensanchez, could you review this?
Since the account API currently only handles the sending of the password change email, this would amount to a test of the student views and built-in Django views. I'd written this test with the intention of verifying that password change *requests* are handled correctly by the API, not that the full password change process (i.e., request to confirmation to complete) works as expected.

I see the value in rewriting this test such that it intercepts the password reset email and ensures that it contains an activation link. However, should I add a more general test of the full process now, or hold off until we revisit the confirmation and completion steps?