Add --line-number option to hg annotate (issue506)
Line numbers are separated from the last annotation element with a colon,
like with many other commands, e.g. (hg) grep or compiler errors.
Idea and tests by FUJIWARA Katsunori.
abort: repository a not found!
255
abort: error: Connection refused
255
abort: repository a not found!
255
abort: destination '../a' already exists
255
abort: repository a not found!
255
destination directory: q
abort: destination 'q' already exists