Improved "Share" function for reviews

Similar to how Frame.io works, thinking on how we utilize it for reviewing client videos, most of our clientele are not very technically savvy, so would love to see some more customization to simplify shared assets. Allowing things like watermarking, removing the ability to download assets, set “comments” as the default side panel vs the details of the file, things like that would go a long way to allowing us to use Shade more internally and with our clients.