This commit does two main things:
- adds textboxes to the send yourself a test page, so you can replace
((name)) with ‘Chris’, or whatever your name is
- rejigs the send page a bit to make it clearer what the CSV upload is
for and how to use it
The idea being that, since most users go into ‘send yourself a test’
first, it teaches them about how placeholders work by making them do the
replacing themselves.
