Added function to calculate absolute value of ulm2

Samo Penic

2018-06-26 0661f62a1a4b5bc87310421d198e7df8538c7363

 src/initial_distribution.c

@@ -112,7 +112,7 @@
        vesicle->sphHarmonics=NULL;
    }

    
   vesicle->tlist->a0=sqrt(3)/4*pow((vesicle->tape->dmax+1.0)/2.0,2);  
    return TS_SUCCESS;

}