[kpropertiesdialog] add icons for the size section

Summary:
add "refresh" and "stop" icons for the buttons in the "size" section

Test Plan: Open properties of a folder and see those icons under "General/size"

Reviewers: VDG, ngraham, GB_2

Reviewed By: VDG, ngraham, GB_2

Subscribers: kde-frameworks-devel

Tags: Frameworks, Dolphin, VDG

Differential Revision: https://phabricator.kde.org/D23969