READWRITE - READ or WRITE a triangulated model

readModel		Read a model in the form produced by writeModel
writeModel		Write a model to a file

Function Prototypes:
Model *readModel (FILE *fp);
void writeModel (Model *m, FILE *fp);

readModel:
Input:
fp		file pointer to file containing model

writeModel:
Input:
m		pointer to Model
fp		file pointer

Author:  Jack K. Cohen, Center for Wave Phenomena, 09/21/90
Modified:  Dave Hale, Center for Wave Phenomena, 11/30/90
	Converted representation of model from ascii to binary for speed.
	Added code to read attributes.
Modified (writeModel):  Craig Artley, Center for Wave Phenomena, 04/08/94
	Corrected bug;  previously the edgeuses and vertextuses of the
	exterior face were not written.