add multi-scale multi-windows block-matching src
Merge branch 'master' into fusion
added a function corresponding_roi in rpc_utils module
sanity check before cropping: coordinates have to be int
fix non integer crop
several changes in the pointing_accuracy module:

- rescaling of rotation and shear parameters for the optimisation, by
  a factor 1e6, to make them less sensitive
- center of the rotation changed to the center of the big image (20000,
  20000)
- other (better ?) implementation of the bfgs algorithm: fmin_l_bfgs_b
  instead of fmin_bfgs
- the evaluation_from_estimated_F function now returns the mean of the
  algebric distances between keypoints and their epipolar lines. Thus we
  can see if there is a bias.
- added a 'linear' version of the cost function (currently not used)
- check if parameters of the cost_function are in a reasonable bounding
  box before evaluating
- in the filtered_sift_matches_roi function, lowered ransac error
  tolerance used to determine whether or not a point is compatible with
  a model, from 1 pix to .3 pix
measure the precision of a fundamental matrix against a set of matches
with L1 norm instead of L_inf