Fixed std::floor

std::floor should only be used with double. With int it makes no sense
and do not compile on blue gene

src/multicolvar/MultiColvar.cpp

@@ -354,9 +354,9 @@ void MultiColvar::threeBodyNeighborList( const SwitchingFunction& sf ){
           if( w<getNLTolerance() ){
               // Deactivate all tasks involving i and j
               for(unsigned k=0;k<getCurrentNumberOfActiveTasks();++k){
-                  unsigned ind=std::floor( getActiveTask(k) / decoder[0] );
+                  unsigned ind=( getActiveTask(k) / decoder[0] );
                   if( ind!=i ) continue;
-                  unsigned ind2=std::floor( (getActiveTask(k) - ind*decoder[0]) / decoder[1] );
+                  unsigned ind2=( (getActiveTask(k) - ind*decoder[0]) / decoder[1] );
                   if( ind2!=j ) continue;
                   inactive_tasks[k] = 1;
               }

src/multicolvar/MultiColvarBase.cpp

@@ -182,7 +182,7 @@ bool MultiColvarBase::setupCurrentAtomList( const unsigned& taskCode ){
      natomsper=current_atoms.size();
      unsigned scode = taskCode;
      for(unsigned i=0;i<ablocks.size();++i){
-        unsigned ind=std::floor( scode / decoder[i] );
+        unsigned ind=( scode / decoder[i] );
         current_atoms[i]=getBaseQuantityIndex( ablocks[i][ind] );
         scode -= ind*decoder[i]; 
      }

src/multicolvar/MultiColvarFunction.cpp

@@ -234,7 +234,7 @@ void MultiColvarFunction::addStoredDerivative( const unsigned& jout, const unsig
       unsigned jindex = offset + base_index; 
       plumed_dbg_assert( jindex<3*getNumberOfAtoms() );
       addElementDerivative( jout*getNumberOfDerivatives() + jindex, der );
-      unsigned iatom = std::floor( jindex / 3 );
+      unsigned iatom = ( jindex / 3 );
       atoms_with_derivatives.activate( iatom );
   }
 }