Revert "Revert "Get rid of KDELibs4Support""
Summary: This reverts commit 55603160. "Get rid of KDELibs4Support" was reverted because Can* methods of PowerManagement class returned incorrect values due to async DBus calls. Use blocking DBus calls now. Reviewers: davidedmundson, broulik, #plasma Reviewed By: davidedmundson, #plasma Subscribers: plasma-devel Tags: #plasma Differential Revision: https://phabricator.kde.org/D11744