Move services for collecting items to Finders

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Update tests and fix Finders readme

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
 Merge branch 'refacoring/selectors' into 'master'

Refacoring: Finders

Services -> change data
Finders -> select data