/// Adds new entity with DateTime.UtcNow to the list of files.
///
/// Example: file "abc.txt" with content "qwe" (v1) was replaced with "rty" (v2), and then was replaced with "qwe" (v3) again.
/// The client should <see cref="UploadNewContent(string, byte[], string)"/> for v1 and v2, and then call this method (passing v1 FileInfo to it) for v3.