Decided to do another rapid fire build. Wanted a bug fix up, but there's some other cool stuff here...
Fix for elite structure not unlocking properly if playing on rookie.
Added support for help videos on unlocks and tooltips.
Added video for elite structure unlock.
Improved/simplified tooltips for structures.
Improved tooltips for structure upgrade, and added comparison.
Adjustments to artillery tower attack rate and damage.
Allowed same item to be placed into primary and elite slot.