File debian.source.lintian-overrides of Package owncloud

# needed for Debian 8.0 to finsh a build in obs.
# FIXME: all that should be warnings in obs, as they are in s2 and local builds.
owncloud source: source-is-missing
owncloud source: license-problem-json-evil
owncloud source: version-substvar-for-external-package