Fix wrong return type in normal()
Merge branch '3d'
Add new Primitive class + loading function to load Primitive arrays from file
Change loading function to take a path instead of a python file
Take as input the project directory, not the project file
Load Gt primitive set
Clean code
Add io package:
  - readPointCloudFromPly
  - readPointAssignementFromFiles
Now load point cloud and ground truth assignement
Compute and display the distance between primitives and points as histogram
Fix the exportPrimitive functions, that wasn't applying the -y flip
Now recompute the GT PDF from the GT histogram and display behind it
Merge remote-tracking branch 'origin/master' into 3d
- added setgment.h to cmakelist
- change plane getdist and project to use normal instead of dir.
- changed plane to store x0,n
- added constructor that takes an eignedecomposition as input to line and planeprimitive
- changed fitlinearprimitive to call this constructor