Implemented the Boundary Intersection (BI) decomposition method.
Merge branch 'multi_objective' of ssh://localhost:2000/p/pagmo/code into multi_objective
python tests working again
Implemented compute_ideal() and compute_nadir() methods in population
It is now possibile to select the weight generation methods in PaDe between RANDOM, GRID and LOW_DISCREPANCY
In PaDE the topology is now build according to the distance between weight vectors.
Implemented a neighbourhood class to calculate those distances.
Fixed bug in decomposition problem: now bounds are set according to the original problem.
code review: partial
Merge branch 'multi_objective' of ssh://git.code.sf.net/p/pagmo/code into multi_objective
code review: partial 2
pade: code review finished
Merge branch 'development' into multi_objective