added the icgem method to export models; type of model loaded is determined from model filename extension; fixed bug in the load_icgem function when the error model was zero
added the icgem method to export models; type of model loaded is determined from model filename extension; fixed bug in the load_icgem function when the error model was zero

jgte/orb,jgte/orb,jgte/orb,jgte/orb,jgte/orb