message: Arquebusier cannot upgrade to Grenadier
diff: <UnitClassUpgradeType>UNITCLASS_MUSKETMAN</UnitClassUpgradeType>
  <bUnitClassUpgrade>1</bUnitClassUpgrade>
  </UnitClassUpgrade>
  - <UnitClassUpgrade>
  - <UnitClassUpgradeType>UNITCLASS_GRENADIER</UnitClassUpgradeType>
  - <bUnitClassUpgrade>1</bUnitClassUpgrade>
  - </UnitClassUpgrade>
  </UnitClassUpgrades>
  <UnitAIs>
  <UnitAI>
  <UnitClassUpgradeType>UNITCLASS_MUSKETMAN</UnitClassUpgradeType>
  <bUnitClassUpgrade>1</bUnitClassUpgrade>
  </UnitClassUpgrade>
  - <UnitClassUpgrade>
  - <UnitClassUpgradeType>UNITCLASS_GRENADIER</UnitClassUpgradeType>
  - <bUnitClassUpgrade>1</bUnitClassUpgrade>
  - </UnitClassUpgrade>
  </UnitClassUpgrades>
  <UnitAIs>
  <UnitAI>
  <UnitClassUpgradeType>UNITCLASS_MUSKETMAN</UnitClassUpgradeType>
  <bUnitClassUpgrade>1</bUnitClassUpgrade>
  </UnitClassUpgrade>
  - <UnitClassUpgrade>
  - <UnitClassUpgradeType>UNITCLASS_GRENADIER</UnitClassUpgradeType>
  - <bUnitClassUpgrade>1</bUnitClassUpgrade>
  - </UnitClassUpgrade>
  </UnitClassUpgrades>
  <UnitAIs>
  <UnitAI>
  <UnitClassUpgradeType>UNITCLASS_MUSKETMAN</UnitClassUpgradeType>
  <bUnitClassUpgrade>1</bUnitClassUpgrade>
  </UnitClassUpgrade>
  - <UnitClassUpgrade>
  - <UnitClassUpgradeType>UNITCLASS_GRENADIER</UnitClassUpgradeType>
  - <bUnitClassUpgrade>1</bUnitClassUpgrade>
  - </UnitClassUpgrade>
  </UnitClassUpgrades>
  <UnitAIs>
  <UnitAI>
  <UnitClassUpgradeType>UNITCLASS_MUSKETMAN</UnitClassUpgradeType>
  <bUnitClassUpgrade>1</bUnitClassUpgrade>
  </UnitClassUpgrade>
  - <UnitClassUpgrade>
  - <UnitClassUpgradeType>UNITCLASS_GRENADIER</UnitClassUpgradeType>
  - <bUnitClassUpgrade>1</bUnitClassUpgrade>
  - </UnitClassUpgrade>
  </UnitClassUpgrades>
  <UnitAIs>
  <UnitAI>
  <UnitClassUpgradeType>UNITCLASS_MUSKETMAN</UnitClassUpgradeType>
  <bUnitClassUpgrade>1</bUnitClassUpgrade>
  </UnitClassUpgrade>
  - <UnitClassUpgrade>
  - <UnitClassUpgradeType>UNITCLASS_GRENADIER</UnitClassUpgradeType>
  - <bUnitClassUpgrade>1</bUnitClassUpgrade>
  - </UnitClassUpgrade>
  </UnitClassUpgrades>
  <UnitAIs>
  <UnitAI>
  