(PE-593) Own files correctly on SLES

Previously no defattr was set for the files section in the spec file for
rubycas-server. This caused a mountain of spammy errors from sles during
install. This commit adds a defattr of root and root for owner and group, that
should resolve this issue.
Merge pull request #16 from haus/ticket/pe_593_add_defattr

Ticket/pe 593 add defattr