Track downloads

[travisvalentine]

This does the following:

• Checks to see if the user can download a theme before showing the download button. What's checked? If the user subscribed to the theme (aka they paid), and if they have downloaded the theme less than 5 times.
• Creates a download object for the theme and user when the user goes to buy the theme. If the download is created, we redirect to the file_package_url which triggers the actual download.

[wallawe]

Just now seeing this. Good stuff