Add dockerfile generation support

Visual studio has a great option named "Add docker support" which automatically generates the dockerfile for you. Since it also lists all csproj files that need to be copied (to make layer caching working) it need to be regenerated when csproj files are added or removed.

We currently have a special guy with Visual Studio which regenerates dockerfiles for us (when he's unavailable, we manually edit them, which is quite inconveinient).

I'd like to have this feature in Rider and/or as a standalone feature as well. It would be great to have it.