New version of Benchmark

• The code points to the pre-computed evaluation recently made available.
• This new version implements the measures used in the PAMI submission and in the following paper:
  Jordi Pont-Tuset and Luc Van Gool
  Boosting Object Proposals: From Pascal to COCO
  International Conference on Computer Vision (ICCV) 2015
• The databases are handled using the gt_wrappers presented in the ICCV code.