[ros-svn] 13656: Don't use svn command line tool to getrevision number

[Ge van Geldorp]

> From: [e-mail]
>
> Don't use svn command line tool to get revision number
> XML code stolen from the xmlbuildsystem branch, we need
> to merge this when merging the xmlbuildsystem back into trunk

If you get weird error messages when svn up'ing in reactos/tools on Linux,
remove reactos/tools/buildno. "reactos/tools/buildno" used to be an
executable, now it's a directory. Doing a "make clean" first and then a "svn
up" works ok. Windows shouldn't be a problem, there is no name conflict
there as the old executable was named buildno.exe.

Gé van Geldorp.