message: Trim starting `/` from relative entry path
  While calculating the relative path, trim away the starting `/`. Otherwise,
  `dest.join` ends up ignoring `dest` altogether and tries to create the directory
  under root (say `/posts`).
diff: @@ -175,6 +175,7 @@ pub fn build(config: &Config) -> Result<()> {
  let relative = try!(entry_path.split(source_str)
  .last()
  + .map(|s| s.trim_left_matches("/"))
  .ok_or(format!("Empty path")));
  if try!(entry.metadata()).is_dir() {
  