Removed check for source normals, since only the target cloud is required to have normals.
Fixed MSVC linker crash.

* Linking pcl_features hit 4GB memory limit in release mode. Disabled whole program optimization and link-time code generation as a workaround.
Corrected initial traversal index

Initial index was wrong when multiple viewports are active.
Add: support IFS file format
Merge pull request #345 from jakobwilm/transformation_estimation_fix

Removed check for source normals
Merge pull request #350 from kwaegel/msvc_linker_fix

Fixed MSVC linker crash.
Merge pull request #354 from nizar-sallem/ifs_support

Add: support IFS file format
Add: load pcl::PolygonMesh from IFS files
Fix: documentation
Update: simplify the API and the code

No deprecated inhere since the methods are private and only used
internally.
Update: clean up around range_grid
Add: ability to load a PolygonMesh from PLY files
Fix: documentation
Merge pull request #356 from nizar-sallem/ifs_support

Add: load pcl::PolygonMesh from IFS files
const correctness fixes
Added i increment.
Fix opengl headers for Mac osX
small bugfix for init of thread number
fix: libc++ is more picky when it comes to const methods
Fix: provide a cast operator to unisgned char to fix libc++ compile issue