[PATCH] make mergeinfo diagram column headings l10n friendly

Hello,

I found the following output of "svn mergeinfo" troublesome to localize.

    youngest last repos.
    common full tip of path of
    ancestor merge branch branch

    2 6
    | |
       --| |------------ branches/branch1
      / /
     / /
  -------| |------------ trunk
              | |
              5 6

Would something like this not be better?

    youngest common ancestor
    | last full merge
    | | tip of branch
    | | | repository path

    2 6
    | |
       --| |------------ branches/branch1
      / /
     / /
  -------| |------------ trunk
              | |
              5 6

A patch to this effect is attached for consideration.

[[[
make mergeinfo diagram column headings l10n friendly

* subversion/svn/mergeinfo-cmd.c
  (mergeinfo_diagram): use one line per column heading and
   vertical lines, leaving room for l10n
]]]