Fix Enrollment Email UI/UX

@jrbl @caesar2164 

Fixed enrollment email UI in Studio. The list of changes is as follows:
    - Test Email functionality: can now send yourself a test email from studio
    - Set default template button: can now click a button to replace email
        with the default template
    - UI changes: html ordering and structuring
                  Got rid of enable_default_email button. Pushed this feature
                  to the default template button

Things to note:
    - default template is stanford-specific.
    - minor test changes (since enable_default_email field is gone now)

![screen shot 2014-07-30 at 12 48 48 pm](https://cloud.githubusercontent.com/assets/3598201/3755213/a65ef2ce-1822-11e4-9b63-d01e16be444f.png)
![screen shot 2014-07-30 at 12 49 07 pm](https://cloud.githubusercontent.com/assets/3598201/3755214/a65f7c30-1822-11e4-8c06-cfdc32c476af.png)
![screen shot 2014-07-30 at 12 48 28 pm](https://cloud.githubusercontent.com/assets/3598201/3755215/a66022e8-1822-11e4-8005-c7200f417886.png)

@jrbl there are other places in the platform where work is only saved when
it's made live (e.g. course updates), so this isn't the only place that
happens.  Ideally everything would have a way to save a draft, but it's
most important for cases where the work is complex, and can't be easily
copy-pasted (e.g. many settings fields).  So I think it's tolerable for
this email to only be save-able when it goes live.  In practice, it's easy
to copy-paste from a draft saved locally. (Whereas the same isn't true for
a problem w/ a setting screen etc.)


On Mon, Aug 4, 2014 at 9:42 AM, Joe Blaylock <notifications@github.com>
wrote:

> In cms/static/js/views/settings/main.js:
>
> > +            subject = this.pre_enrollment_email_subject_elem.val();
> > +            message = this.pre_enrollment_email_elem.val();
> > +        } else {
> > +            subject = this.post_enrollment_email_subject_elem.val();
> > +            message = this.post_enrollment_email_elem.val();
> > +        }
> > +
> > +        $.post("/settings/send_test_
> enrollment_email",
> > +               {
> > +                 subject: subject,
> > +                 message:message,org:this.model.get('org'),
> > +                 number: this.model.get('course_id'),
> > +                 run: this.model.get('run'),
> > +               },
> > +               function (data) {
> > +                   alert(gettext("Test email sent! Please check your inbox. Don't forget to save!"));
>
> The only way to save your work is to make it live, i.e., to set the email
> as the one that gets used? There's no way to save work that's not complete
> yet? The email model object doesn't have a flag to indicate liveness?
>
> —
> Reply to this email directly or view it on GitHub
> <https://github.com/Stanford-Online/edx-platform/pull/94/files#r15765544>.
>