Reverted VolumeDefaultFT3 to pre X2315 code (thus ensuring no conversion to metric values), added some warning messages if Grate Area, Evaporation Area or BoilerVolume were missing from ENG file.
git-svn-id: http://svn.uktrainsim.com/svn/openrails/trunk@2336 a9f3cfff-6c41-7446-b0ca-052bd761e6eb