Add a camera to the Ion Cannon. Fixes #5058.
Make nuke flight time independent from map size.
Add a camera to the nuke.
Change D2K airstrike shroud reveal to match TD.
Support indefinite beacon duration for support powers that remove the beacon on completion.
Persist the nuke beacon until detonation.
Fix GDI03 airstrike power.
Update changelog.
Merge pull request #5066 from pchote/weapon-cameras

Superweapon tweaks