Remaining Classes: Keys stored as constants
Remaining Classes: Keys stored as constants

For classes - KateGlobalConfig, KateDocumentConfig & KateRendererConfig:
Keys extracted & stored as constants.
This improves maintainability.

This TODO is now resolved. So, removed the TODO comment.

REVIEW: 114000

hlamer/kate,jfmcarreira/kate,jfmcarreira/kate,hlamer/kate,cmacq2/kate,hlamer/kate,cmacq2/kate,sandsmark/kate,hlamer/kate,sandsmark/kate,DickJ/kate,sandsmark/kate,DickJ/kate,hlamer/kate,hlamer/kate,hlamer/kate,jfmcarreira/kate,hlamer/kate,cmacq2/kate,sandsmark/kate,DickJ/kate,DickJ/kate,hlamer/kate,hlamer/kate