Rails 5 export CSV problem

Hello,
After upgrading to Rails 5, the export CSV has broken.

Fixed it changing 
```
format.csv do
   send_data @dataclip.csv_string, type: Mime::CSV, disposition: "attachment; filename=#{@dataclip.token}.csv"
end
```
to
```
format.csv do
   send_data @dataclip.csv_string, type: Mime[:csv], disposition: "attachment; filename=#{@dataclip.token}.csv"
end
```