We want to limit the number of rows someone can have in a job, because
it gets too slow to process the file otherwise.
This should be the first error that a user sees, because we can’t work
out if there are other errors until they’ve got the file down to a
processable size.
This also means adding a message to say that the file can’t be displayed
if it doesn’t contain any processed rows.
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https://www.pivotaltracker.com/story/show/129830161
a32dcbf8e3