Create model button has popup blocked

[jorgehpo]

When I try to download a model (create model button), the popup is blocked by default. Maybe there's a better way to download a file, rather than opening a popup. Some users might think this is a bug.

[yamsgithub]

We need to check if pop-up is blocked and enable it.

[nandukalidindi]

A Download button is provided for the user to click on once the model is ready. This method is chosen because difficulty to open a new window inside an AJAX block. Most of the articles suggested to provide user interaction.

[nandukalidindi]

Fixed by commit 72031a6