Updating lintian overrides.

bzr revid: p_christ@hol.gr-20090421090642-iv76k9d0ump1r4nf

debian/openerp-server.lintian-overrides

 # Add-on directories needs data directories, and sometimes they are
 # (intentionally) empty, hence overriting the lintian warning.
 openerp-server: package-contains-empty-directory
+# Add-on directoires contain images sometimes, but it's nothing that is
+# worthwile to be splittet out to /usr/share as it's all manual work for each
+# release.
+openerp-server: image-file-in-usr-lib