Assigns the VSprites as the head and tail of the gel list in GfxBase. Links these two gels together as the keystones of the list. If the collHandler vector points to some memory array, sets the BORDERHIT vector to NULL.
INPUTS
head
pointer to the VSprite structure to be used as the gel list head
tail
pointer to the VSprite structure to be used as the gel list tail
GInfo
pointer to the GelsInfo structure to be initialized