Implementation of surface weighting
Implementation of surface weighting

Also fixed total weight normalization

JohnGriffiths/nipype,rameshvs/nipype,carolFrohlich/nipype,grlee77/nipype,pearsonlab/nipype,carolFrohlich/nipype,mick-d/nipype_source,arokem/nipype,dgellis90/nipype,glatard/nipype,pearsonlab/nipype,grlee77/nipype,carolFrohlich/nipype,carlohamalainen/nipype,carolFrohlich/nipype,sgiavasis/nipype,blakedewey/nipype,blakedewey/nipype,JohnGriffiths/nipype,carlohamalainen/nipype,dmordom/nipype,dmordom/nipype,FCP-INDI/nipype,glatard/nipype,iglpdc/nipype,mick-d/nipype_source,blakedewey/nipype,fprados/nipype,dgellis90/nipype,rameshvs/nipype,Leoniela/nipype,Leoniela/nipype,wanderine/nipype,Leoniela/nipype,sgiavasis/nipype,wanderine/nipype,pearsonlab/nipype,arokem/nipype,arokem/nipype,mick-d/nipype,carlohamalainen/nipype,pearsonlab/nipype,dgellis90/nipype,blakedewey/nipype,mick-d/nipype,wanderine/nipype,FCP-INDI/nipype,dmordom/nipype,iglpdc/nipype,wanderine/nipype,grlee77/nipype,gerddie/nipype,gerddie/nipype,gerddie/nipype,mick-d/nipype_source,FCP-INDI/nipype,grlee77/nipype,rameshvs/nipype,FCP-INDI/nipype,mick-d/nipype,dgellis90/nipype,gerddie/nipype,arokem/nipype,fprados/nipype,rameshvs/nipype,JohnGriffiths/nipype,fprados/nipype,iglpdc/nipype,sgiavasis/nipype,glatard/nipype,JohnGriffiths/nipype,sgiavasis/nipype,glatard/nipype,mick-d/nipype,iglpdc/nipype