More useful error/stats information for each Data Box

[shyamperi]

1. In the Datasets views, the status of the each Data Box just says "Error" & there is no easy way to figure out which error it is as the subsequent runs overwrite the message
   Just like the classic if the Meta can hold proper information about each runs, it will be very useful.

2. Information such as how many pages have been scraped, how many records have been inserted, if available will also be very useful.

[frabcus]

At the moment, the tool writes to the Error end point in a very bland way.

In theory it should not do this if the user writes from their script, but I'm not sure how to do it in practice.