Merge pull request #5 from Tw1ddle/master

Add missed dualOptimize calls and mistake in dualOptimize method

src/main/java/no/birkett/kiwi/Solver.java

@@ -246,6 +246,7 @@ public class Solver {
             if(row.add(-delta) < 0.0){
                 infeasibleRows.add(info.tag.marker);
             }
+			dualOptimize();
             return;
         }
 
@@ -254,6 +255,7 @@ public class Solver {
             if(row.add(delta) < 0.0){
                 infeasibleRows.add(info.tag.other);
             }
+			dualOptimize();
             return;
         }
 
@@ -528,7 +530,7 @@ public class Solver {
                 if(entering.getType() == Symbol.Type.INVALID){
                     throw new InternalSolverError("internal solver error");
                 }
-                rows.remove(entering);
+                rows.remove(leaving);
                 row.solveFor(leaving, entering);
                 substitute(entering, row);
                 rows.put(entering, row);