Fix Eigen crash of memory alignment

#0  0xb29183ee in ?? () from /lib/libc.so.6
iralabdisco#1  0x080c85a2 in Eigen::internal::handmade_aligned_free(void*) ()
iralabdisco#2  0x080c85ef in Eigen::internal::aligned_free(void*) ()
iralabdisco#3  0x080cf4d8 in void Eigen::internal::conditional_aligned_free<true>(void*) ()
iralabdisco#4  0x080d5a6f in void Eigen::internal::conditional_aligned_delete_auto<float, true>(float*, unsigned int) ()
iralabdisco#5  0x080d350e in Eigen::DenseStorage<float, -1, -1, -1, 0>::~DenseStorage() ()
iralabdisco#6  0x080ce018 in Eigen::PlainObjectBase<Eigen::Matrix<float, -1, -1, 0, -1, -1> >::~PlainObjectBase() ()
iralabdisco#7  0x080ce030 in Eigen::Matrix<float, -1, -1, 0, -1, -1>::~Matrix() ()
iralabdisco#8  0x080c4a65 in LaserscanMerger::scanCallback(boost::shared_ptr<sensor_msgs::LaserScan_<std::allocator<void> > const> const&, std::string) ()

launch/laserscan_multi_merger.launch

@@ -9,7 +9,7 @@
             angle_max: 2.36
             angle_min: -2.36
             cloud_destination_topic: /merged_cloud
-            destination_frame: /base_footprint
+            destination_frame: base_footprint
             laserscan_topics: /scan /pepper/laser
             range_max: 4.0
             range_min: 0.2

src/laserscan_multi_merger.cpp

@@ -55,6 +55,7 @@ class LaserscanMerger
     string cloud_destination_topic;
     string scan_destination_topic;
     vector<string> laserscan_topics;
+    Eigen::MatrixXf points;
 };
 
 void LaserscanMerger::reconfigureCallback(laserscan_multi_mergerConfig &config, uint32_t level)
@@ -184,7 +185,6 @@ void LaserscanMerger::scanCallback(const sensor_msgs::LaserScan::ConstPtr& scan,
 
 		point_cloud_publisher_.publish(merged_cloud);
 
-		Eigen::MatrixXf points;
 		getPointCloudAsEigen(merged_cloud,points);
 
 		pointcloud_to_laserscan(points, &merged_cloud);