add flag -S to copy sources to <GEM_DEB_MONOTONE>/sources
add flag -S to copy sources to <GEM_DEB_MONOTONE>/sources


Former-commit-id: c09af31066158b5613e7ac07e47932abfe6983e8
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine