Changes cost format in table view

[qduk]

While working with a customer, two concerns came up about the format of some data in certian columns of the Contract list view. I figure I make a PR here to see if these would be welcome changes. If these are liked, I'll do the same for the 2.0 version.

This PR does two things:

1. Comma separated cost in the "cost" column
2. Reformats the date in the "Month-Day-Year` format.
   

[progala]

Thanks @qduk . I like the change to the cost format. As for the date, what is the rationale behind the change? Existing format is consistent across Nautobot and conforms to the ISO 8601 standard.

[qduk]

Thanks @qduk . I like the change to the cost format. As for the date, what is the rationale behind the change? Existing format is consistent across Nautobot and conforms to the ISO 8601 standard.

I think that was just my own bias creeping in. It definitely makes sense to leave it as is. I can remove that part from the PR.

[qduk]

@progala Removed Date formatting.

[progala]

LGTM