Added constant volume plugin (partially)

Samo Penic

2019-03-08 77a2c7de0dd6563a30467fa2e73f02ec9f4c3deb

 src/initial_distribution.c

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

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

}