Incinerator model changed to gold sentinel. Security Drones adjusted to function as early game rushers/scouts, damage&HP nerfed

Sentinels getting stuck in expansion bases should be fixed. Hero and Unit upgrades are split to encourage tactical usage Sentinels now have Damage, Shield, and HP upgrade tiers. Units and hero shielding should be upgradeable. Garrison pad disabled, it isn't behaving correctly and extremely bugged.

Note: Base turrets are dedicated to the unit type they are strong against, so AA turrets can't hit ground, AT can't hit air, etc. Base turrets and deployable turret fixed, rotation angles were incorrect.