Fixed to select correct library under 32 bit.

Library path was hard coded and this caused a problem that incorrect library file was selected under 32 bit environment.
This commit add some codes to choose corresponding library file according to the build environment.
Fix warnings in 2d/edge.h

> edge.h:292:48: warning: unused parameter 'output' [-Wunused-parameter]
Fix warnings in 2d/test_2d.cpp

> test_2d.cpp:258:19: warning: comparison of integers of different signs: 'int' and 'uint32_t' (aka 'unsigned int') [-Wsign-compare]
> test_2d.cpp:259:21: warning: comparison of integers of different signs: 'int' and 'uint32_t' (aka 'unsigned int') [-Wsign-compare]
Fix warnings in ml/svm.cpp

> svm.cpp:3266:9: warning: explicitly assigning a variable of type 'int' to itself [-Wself-assign]
Fix warnings in ml/svm_wrapper.cpp

> svm_wrapper.cpp:140:21: warning: comparison of integers of different signs: 'int' and 'size_type' (aka 'unsigned long') [-Wsign-compare]
> svm_wrapper.cpp:141:23: warning: comparison of integers of different signs: 'int' and 'size_type' (aka 'unsigned long') [-Wsign-compare]
> svm_wrapper.cpp:157:21: warning: comparison of integers of different signs: 'int' and 'size_type' (aka 'unsigned long') [-Wsign-compare]
> svm_wrapper.cpp:158:23: warning: comparison of integers of different signs: 'int' and 'size_type' (aka 'unsigned long') [-Wsign-compare]
> svm_wrapper.cpp:229:23: warning: comparison of integers of different signs: 'int' and 'size_type' (aka 'unsigned long') [-Wsign-compare]
> svm_wrapper.cpp:469:21: warning: comparison of integers of different signs: 'int' and 'size_type' (aka 'unsigned long') [-Wsign-compare]
> svm_wrapper.cpp:478:23: warning: comparison of integers of different signs: 'int' and 'size_type' (aka 'unsigned long') [-Wsign-compare]
> svm_wrapper.cpp:815:17: warning: comparison of integers of different signs: 'int' and 'size_type' (aka 'unsigned long') [-Wsign-compare]
> svm_wrapper.cpp:913:21: warning: comparison of integers of different signs: 'int' and 'size_type' (aka 'unsigned long') [-Wsign-compare]
> svm_wrapper.cpp:915:23: warning: comparison of integers of different signs: 'int' and 'size_type' (aka 'unsigned long') [-Wsign-compare]
Fix warnings in ml/decision_tree_trainer.hpp

> decision_tree_trainer.hpp:287:41: warning: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long') [-Wsign-compare]
> decision_tree_trainer.hpp:301:49: warning: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long') [-Wsign-compare]
Fix warnings in filters/voxel_grid.h

> voxel_grid.h:208:9: warning: field 'filter_limit_negative_' will be initialized after field 'min_points_per_voxel_' [-Wreorder]
> voxel_grid.h:535:9: warning: field 'filter_limit_negative_' will be initialized after field 'min_points_per_voxel_' [-Wreorder]
Fix warnings in compression/organized_pointcloud_compression.hpp

> organized_pointcloud_compression.hpp:316:11: warning: variable 'disparityShift' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
Fix warnings in octree/octree_pointcloud_adjacency_container.h

> octree_pointcloud_adjacency_container.h:98:33: warning: unused parameter 'new_point' [-Wunused-parameter]
> octree_pointcloud_adjacency_container.h:179:7: warning: 'pcl::octree::OctreePointCloudAdjacencyContainer<pcl::PointXYZRGB, pcl::SupervoxelClustering<pcl::PointXYZRGB>::VoxelData>::getSize' hides overloaded virtual function [-Woverloaded-virtual]
Fix warnings in octree/octree_pointcloud_adjacency.hpp

> octree_pointcloud_adjacency.hpp:60:21: warning: comparison of integers of different signs: 'int' and 'size_t' (aka 'unsigned long') [-Wsign-compare]
Fix warnings in stereo/stereo_matching.h

> stereo_matching.h:511:14: warning: private field 'lut_' is not used [-Wunused-private-field]
Fix warnings in stereo/stereo_matching.cpp

> stereo_matching.cpp:158:20: warning: comparison of integers of different signs: 'uint32_t' (aka 'unsigned int') and 'int' [-Wsign-compare]
> stereo_matching.cpp:158:46: warning: comparison of integers of different signs: 'uint32_t' (aka 'unsigned int') and 'int' [-Wsign-compare]
> stereo_matching.cpp:237:22: warning: comparison of integers of different signs: 'uint32_t' (aka 'unsigned int') and 'int' [-Wsign-compare]
> stereo_matching.cpp:237:51: warning: comparison of integers of different signs: 'uint32_t' (aka 'unsigned int') and 'int' [-Wsign-compare]
> stereo_matching.cpp:321:20: warning: comparison of integers of different signs: 'uint32_t' (aka 'unsigned int') and 'int' [-Wsign-compare]
> stereo_matching.cpp:321:47: warning: comparison of integers of different signs: 'uint32_t' (aka 'unsigned int') and 'int' [-Wsign-compare]
> stereo_matching.cpp:482:38: warning: comparison of integers of different signs: 'uint32_t' (aka 'unsigned int') and 'int' [-Wsign-compare]
> stereo_matching.cpp:482:62: warning: comparison of integers of different signs: 'uint32_t' (aka 'unsigned int') and 'int' [-Wsign-compare]
Fix warnings in commor/bearing_angle_image.cpp

> bearing_angle_image.cpp:109:21: warning: comparison of integers of different signs: 'int' and 'unsigned int' [-Wsign-compare]
Fix warnings in common/point_types_conversion.h

> point_types_conversion.h:364:31: warning: comparison of integers of different signs: 'unsigned int' and 'int' [-Wsign-compare]
> point_types_conversion.h:366:33: warning: comparison of integers of different signs: 'unsigned int' and 'int' [-Wsign-compare]
Fix warnings in sample_consensus/sac_model_registration_2d.h

> sac_model_registration_2d.h:154:65: warning: unused parameter 'cloud' [-Wunused-parameter]
> sac_model_registration_2d.h:182:65: warning: unused parameter 'cloud' [-Wunused-parameter]
> sac_model_registration_2d.h:183:63: warning: unused parameter 'indices' [-Wunused-parameter]
Fix warnings in sample_consensus/sac_model_registration_2d.hpp

> sac_model_registration_2d.hpp:47:88: warning: unused parameter 'samples' [-Wunused-parameter]
Fix warnings in io/tar.h

> tar.h:94:43: warning: unused parameter 'tar_filename' [-Wunused-parameter]
> tar.h:95:50: warning: unused parameter 'cloud' [-Wunused-parameter]
> tar.h:96:43: warning: unused parameter 'pcd_filename' [-Wunused-parameter]
Fix warnings in io/openni_device.cpp

> openni_device.cpp:437:29: warning: comparison of integers of different signs: 'pcl::int32_t' (aka 'int') and 'XnUInt32' (aka 'unsigned int') [-Wsign-compare]
Fix warnings in io/openni_grabber.cpp

> openni_grabber.cpp:598:21: warning: comparison of integers of different signs: 'int' and 'const unsigned int' [-Wsign-compare]
> openni_grabber.cpp:600:32: warning: comparison of integers of different signs: 'int' and 'const unsigned int' [-Wsign-compare]
> openni_grabber.cpp:703:21: warning: comparison of integers of different signs: 'int' and 'const unsigned int' [-Wsign-compare]
> openni_grabber.cpp:705:32: warning: comparison of integers of different signs: 'int' and 'const unsigned int' [-Wsign-compare]
> openni_grabber.cpp:814:21: warning: comparison of integers of different signs: 'int' and 'const unsigned int' [-Wsign-compare]
> openni_grabber.cpp:816:21: warning: comparison of integers of different signs: 'int' and 'const unsigned int' [-Wsign-compare]
Fix warnings in visualization/hdl_viewer_simple.cpp

> hdl_viewer_simple.cpp:107:55: warning: unused parameter 'startAngle' [-Wunused-parameter]
> hdl_viewer_simple.cpp:108:27: warning: unused parameter 'endAngle' [-Wunused-parameter]
> hdl_viewer_simple.cpp:117:30: warning: unused parameter 'cookie' [-Wunused-parameter]
> hdl_viewer_simple.cpp:127:27: warning: unused parameter 'cookie' [-Wunused-parameter]