0.5.1 Hotfix 2

Change: The default horse power of the iowa class engine

Change: a little tip added to paint panel

Change: maximum range of horn sound

Fix: Ai can't use 460mm turret

Fix: TAB key doesn't work in battle

Fix: ship load error when it contains part whose id is 96

Fix: some error with paint panel

Fix: you can not horn when ship sunk