Upgrading machines results in crashes.

[snowboundmage2]

Posting this here because Alex said Smart! is responsible for the upgrade logic used by Mk++.(https://discordapp.com/channels/799091523173613589/840706876836544512/1014097048854876160)

Mk3 Blender crashes when upgrading to Mk4. This occurs regardless of connections(no inputs/outputs, full inputs/outputs) Mk3>Mk4 refinery upgrade also crashes. Vanilla Blender to Mk2 Blender also crashes. Vanilla Constructor to Mk2 Constructor also crashes. Vanilla Mk3 drill to Mk4 drill doesn't crash. Smelter Mk2 to Smelter Mk3 crashes. Mk3 Constructor to Mk4 Constructor

Engine crash log here: https://pastebin.com/7keH5Cqq

Semi-Related to #74

Mod Config:

• Game Branch: [Experimental]
• Game Type [Steam]
• Game Version [198647]
• Mod Type [Public]
• Mod Version [19.4.449-Test]
• SMM/SML Version [3.3.2]
• Is this in multiplayer (non-private session)? No, Singleplayer
• What other mods are you using? Mk++

Smart! 19.4.447-test crashes the game when upgrading Smart! 19.4.442-test won't let me upgrade, tells me "An identical buildable is already built there!" Smart! 19.5.431-test game crashes while loading a save. Smart! 19.5.407-test crashes the game when upgrading Smart! 19.5.403-test crashes the game when upgrading Smart! 19.3.315-test also crashes the game when upgrading. This is notable because before the game updated to EXP 198647, this worked.

[Supertacoz]

I have encountered this bug while playing in U5, so it is not limited to experimental.