Revision 619 - 2006-07-15:
Added: New database flags for modders:
AdvanceDB:
EitherPrerequisites: Advance just needs one of the prerequisites to be researched. This allows a fluid tech tree like Civ4.

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Update - Revision 1017 - 2009-07-31:
I fixed this so it now works, see this post:
http://apolyton.net/forums/showthread.php?p=5649918#post5649918

BTW it's EitherPrerequisites NOT EitherPrerequisite.

 - Maq

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