Update references to Cycle

Author: clue

src/DetectNegativeCycle.php

@@ -7,6 +7,7 @@
 
 use Fhaculty\Graph\Graph;
 use Fhaculty\Graph\Vertex;
+use Fhaculty\Graph\Walk;
 use Fhaculty\Graph\Exception\NegativeCycleException;
 use Fhaculty\Graph\Algorithm\ShortestPath\MooreBellmanFord as SpMooreBellmanFord;
 
@@ -34,7 +35,7 @@ public function hasCycleNegative()
     /**
      * Searches all vertices for the first negative cycle
      *
-     * @return Cycle
+     * @return Walk
      * @throws UnderflowException if there's no negative cycle
      * @uses AlgorithmSpMooreBellmanFord::getVerticesId()
      */
@@ -72,7 +73,7 @@ public function getCycleNegative()
      * @return Graph
      * @throws Exception if there's no negative cycle
      * @uses AlgorithmDetectNegativeCycle::getCycleNegative()
-     * @uses Cycle::createGraph()
+     * @uses Walk::createGraph()
      */
     public function createGraph()
     {

src/ShortestPath/MooreBellmanFord.php

@@ -3,7 +3,7 @@
 namespace Fhaculty\Graph\Algorithm\ShortestPath;
 
 use Fhaculty\Graph\Edge\Base as Edge;
-use Fhaculty\Graph\Cycle;
+use Fhaculty\Graph\Walk;
 use Fhaculty\Graph\Exception\NegativeCycleException;
 use Fhaculty\Graph\Exception\UnderflowException;
 
@@ -97,7 +97,7 @@ public function getEdges()
         // Check for negative cycles (only if last step didn't already finish anyway)
         // something is still changing...
         if ($changed && $changed = $this->bigStep($edges, $totalCostOfCheapestPathTo, $predecessorVertexOfCheapestPathTo)) {
-            $cycle = Cycle::factoryFromPredecessorMap($predecessorVertexOfCheapestPathTo, $changed, Edge::ORDER_WEIGHT);
+            $cycle = Walk::factoryCycleFromPredecessorMap($predecessorVertexOfCheapestPathTo, $changed, Edge::ORDER_WEIGHT);
             throw new NegativeCycleException('Negative cycle found', 0, NULL, $cycle);
         }
 
@@ -107,7 +107,7 @@ public function getEdges()
     /**
      * get negative cycle
      *
-     * @return Cycle
+     * @return Walk
      * @throws UnderflowException if there's no negative cycle
      */
     public function getCycleNegative()

src/TravelingSalesmanProblem/Base.php

@@ -2,7 +2,7 @@
 
 namespace Fhaculty\Graph\Algorithm\TravelingSalesmanProblem;
 
-use Fhaculty\Graph\Cycle;
+use Fhaculty\Graph\Walk;
 use Fhaculty\Graph\Vertex;
 use Fhaculty\Graph\Edge\Base as Edge;
 use Fhaculty\Graph\Algorithm\Base as AlgorithmBase;
@@ -40,14 +40,14 @@ abstract protected function getVertexStart();
     /**
      * get (first) best circle connecting all vertices
      *
-     * @return Cycle
+     * @return Walk
      * @uses AlgorithmTsp::getEdges()
      * @uses AlgorithmTsp::getVertexStart()
-     * @uses Cycle::factoryFromEdges()
+     * @uses Walk::factoryCycleFromEdges()
      */
     public function getCycle()
     {
-        return Cycle::factoryFromEdges($this->getEdges(), $this->getVertexStart());
+        return Walk::factoryCycleFromEdges($this->getEdges(), $this->getVertexStart());
     }
 
     public function getWeight()