Bump the release number to > 5.03

The inclusion of the Russian translation brings one problem.

The existing man-pages-ru package (http://sourceforge.net/projects/man-pages-ru/) has the release version 5.03 and when this package is installed by the user, it won't get updated via the man-pages-l10n due to the lower NVR (4.17.0).

To solve this issue, the version of your release has to be bigger than the 5.03.