Improve the problems tool view CCBUG: 339839
Summary: Remove text in "Error", "Warning" and "Hint" buttons and move them from the pop-up menu. Add current scope setting to the "Scope" button.
Test Plan: Tests passed; works as expected.
Reviewed By: kfunk
Subscribers: KDevelop, kdevelop-devel
Differential Revision: https://phabricator.kde.org/D799