[Algorit] Do away with an unnecessary cutoff

dune/tectonic/minimisation.hh

@@ -39,11 +39,11 @@ void minimise(Functional const &J, typename Functional::SmallVector &x,
   for (size_t step = 0; step < steps; ++step) {
     SmallVector v;
     J.gradient(x, v);
-    v *= -1;
-
-    if (v.two_norm() < 1e-14) // TODO: Make controllable
+    if (v.two_norm() == 0.0)
       return;
 
+    v *= -1;
+
     descentMinimisation(J, x, v, bisection);
   }
 }