* Implement Einsum reference in nGraph interpreter Signed-off-by: Roman Kazantsev <roman.kazantsev@intel.com> * Apply code-style patch and fix build issues Signed-off-by: Roman Kazantsev <roman.kazantsev@intel.com> * Fix CI build Signed-off-by: Roman Kazantsev <roman.kazantsev@intel.com> * Fix fast build and apply code review feedback Signed-off-by: Roman Kazantsev <roman.kazantsev@intel.com> * Add visitor API tests, check for input type and reduce memory consumption Signed-off-by: Roman Kazantsev <roman.kazantsev@intel.com> * Apply code style Signed-off-by: Roman Kazantsev <roman.kazantsev@intel.com> * Add visitor API tests Signed-off-by: Roman Kazantsev <roman.kazantsev@intel.com>