Update pom version to 5.0.3

git-svn-id: http://talendforge.org/svn/tos/branches/branch-5_0@86097 f6f1c999-d317-4740-80b0-e6d1abc6f99e
[GIT Migration] Removed unnecessary root files on branch branch-5_0 from [tos]
[GIT Migration] migration merge tos/branch-5_0
Merge branch 'maintenance/5.0' into maintenance/5.1