[profiles/package.mask] Mask Plasma 5.0.0
[media-fonts/oxygen-fonts] Version bump. Remove old.

Package-Manager: portage-2.2.10
[x11-libs/libkscreen] Version bump. Remove old.

Package-Manager: portage-2.2.10
[eclass] Handle Plasma 5 release.
[kde-base] Add Plasma 5.0.0
[kde-base] Remove Plasma 4.98.0
[profiles/package.mask] Remove obsolete masks.