Function bdrck::cli::prompt_for_string_confirm

pub fn prompt_for_string_confirm(
    output_stream: Stream, 
    prompt: &str, 
    is_sensitive: bool
) -> Result<String>

Prompt for a string as per prompt_for_string, but additionally have the user enter the value again to confirm we get the same answer twice. This is useful for e.g. password entry.