Fix incompatibility with Boost 1.56

The fix is based on the proposal of Andrew McMahon (@McDamon, #864).
Merge pull request #867 from taketwo/fix-lzf

Fix incompatibility with Boost 1.56
Merge branch 'master' of https://github.com/PointCloudLibrary/pcl
fix the bug in ply_io.cpp to avoid crash when read range_grid ply file