Added missing word and link

Based on the keypoints found we have to +extract+ features (linked tutorial which explains how features work in pcl)
Modify tutorials to point to the new data sources.
Added nurbs cylinder fit with defined axes - first one is used as cylinder axis
Added function declaration for initNurbsCylinderWithAxes
Match PCL style requirements
CPPF Implementation
Formatting.
Added CPPFSignature struct. Modified CMakeLists.txt
added equal3() method to auxiliary.h and added a check to getFullLeavesIntersectedBySphere to prevent inclusion of source point leaf
Remove reference to openni-dev in pkg-config files.

OpenNI packages are not currently shipped with any pkg-config
files. Furthermore, Debian packages libopenni-dev and openni-dev are
currently not coinstallable and provide pkg-config files with
different namings. To workaround these issues, this patch disables
OpenNI check in pkg-config files.

This partially solves issue #221.
Merge pull request #295 from stanislas-brossette/master

Remove reference to openni-dev in pkg-config files.
Merge pull request #297 from georgebrindeiro/patch-1

Added missing word and link
Merge pull request #282 from mszarski/patch-2

NURBS Cylinder Fit Axis Initialization
Merge pull request #262 from taketwo/fix-data-references

Modify tutorials to point to the new data sources
New Version 1.7.1
reformatted according to PCL coding style
Fix compiling error of deprecated template.
vtkRegressionTestImage.h causes missing header compiler error with VS2012 vtk6 without test build turned on. It is not used at all, so just remove it.
Add: processing of alpha channel in color handlers
Fix: issue in ISSKeypoint3D where PointOutT is assumed to be PointInT