General Infrastructure Maintainability: API and EBN

[David Edmundson]

For EBN, personally I don't find myself using it. I think clang / llvm
warnings / new Qt warnings cover a large part of the source code
section.

I've made a task listing everything EBN currently checks. Then
together can mark off what things have other replacement, and what
remaining things are actually still useful:
https://phabricator.kde.org/T12013

David