Investigate differences in KindOfType between Generals and Zero Hour

[Mauller]

While working on merging AiPathfind, i found that the KindOfType Struct has some significant changes between generals and zero hour that might make them incompatible if there are data dependencies.

This needs further investigating.

For now i am leaving the new KINDOF_BLAST_CRATER within the zero hour specific code as building it without RETAIL_COMPATIBLE_PATHFINDING in generals will fail.

KINDOF_AIRFIELD was removed from the Generals KindOfType struct quite low in the struct causing all following enumerations to shift by one.