Moved plugins into separate directory

Samo Penic

2019-02-27 74bf1e608f0c51841876d1f36c47180b4eedc6d4

 src/energy.c

@@ -238,3 +238,7 @@
   return vesicle->tape->F*ddp;      
   
}

void stretchenergy(ts_vesicle *vesicle, ts_triangle *triangle){
   triangle->energy=vesicle->tape->xkA0/2.0*pow((triangle->area/vesicle->tlist->a0-1.0),2);
}