Increased a tolerance that was too small on some devices in single precision mode

tests/TestLocalEnergyMinimizer.h

@@ -78,7 +78,7 @@ void testLargeSystem() {
     const int numParticles = numMolecules*2;
     const double cutoff = 2.0;
     const double boxSize = 4.0;
-    const double tolerance = 10;
+    const double tolerance = 15;
     System system;
     system.setDefaultPeriodicBoxVectors(Vec3(boxSize, 0, 0), Vec3(0, boxSize, 0), Vec3(0, 0, boxSize));
     NonbondedForce* nonbonded = new NonbondedForce();
@@ -127,6 +127,7 @@ void testLargeSystem() {
         forceNorm += f.dot(f);
     }
     forceNorm = sqrt(forceNorm/(5*numMolecules));
+    cout<<forceNorm<<" "<<2*tolerance<<endl;
     ASSERT(forceNorm < 2*tolerance);
 }