Support for setting tags read only.

[lkarsten]

In the case of using filebin for file distribution to multiple parties, it would be very beneficial to be able to set a tag as read only.

For a shared tag, it would be possible for someone that has the link to replace uploaded binaries with trojaned ones.

It could work like a one-way setting. You can set it, but there is no way of making the tag readable again.

It should not prohibit the tag from being deleted. Usually you can just create a new tag with the same files if the tag is deleted unintentionally/maliciously.

[espebra]

Good idea. It can be fixed after #10 has been taken care of.

[espebra]

This has been fixed in https://github.com/espebra/filebin2, just four-and-a-half years later. Currently available in the development environment at https://dev.filebin.net/.