Various fixes to our upgrade logic (#536)

Stuff broke over time, especially with the major changes we made leading
up to 2.3. We should test with older saves if/when we make large changes
in the future.

Fixes #532

src/utils/JSONReviver.ts

@@ -34,6 +34,9 @@ export function Reviver(_key: string, value: unknown): any {
       case "Industry":
         console.warn("Converting a corp from pre-2.3");
         return value.data; // Will immediately be overwritten by v2.3 save migration code
+      case "Employee":
+        console.warn("Converting a corp from pre-2.2");
+        return value.data; // Will immediately be overwritten by v2.3 save migration code
     }
     // Missing constructor with no special handling. Throw error.
     throw new Error(`Could not locate constructor named ${value.ctor}. If the save data is valid, this is a bug.`);