New interface for cacheable objects

Signed-off-by: selmeci <selmeci.roman@gmail.com>
Worker cache return value of command evaluation only if cache UID is
returned

Signed-off-by: selmeci <selmeci.roman@gmail.com>
Added element type specification

Signed-off-by: selmeci <selmeci.roman@gmail.com>
Added addresses for element type service

Signed-off-by: selmeci <selmeci.roman@gmail.com>