Fix cnc's nuke not damaging air units (a regression from a recent commit to remove its PerCell damage model)
don't count units twice and forget about buildings

closes #4283
Merge pull request #4288 from Mailaender/stats-fix

Fix death count in observer stats
Merge pull request #4286 from ScottNZ/bleed

Fix cnc's nuke not damaging air units (a regression from a recent commit...
Merge pull request #4287 from pchote/shroud

Rewrite shroud renderer.
Convert SmudgeLayer to sequences.
Use the original D2K craters.
Update CHANGELOG.
Fix typos spelling in changelog.