Added the mixin ScoreMixin which numerically computes the score function q.
Minor bug fixes to score methods + example calculation notebook.
Merge pull request #13 from ihincks/feature-score

Included ability to compute the score function numerically by adding ScoreMixin
Added RB example for ScoreMixin.
Changed init file to address #14.
Minor fixes to models.
Fixed mistake w/ bad A, B.
Minor changes to ScoreMixin example.
Merge branch 'master' into feature-score

Conflicts:
	src/qinfer/__init__.py
	src/qinfer/test_models.py
Merge pull request #16 from csferrie/feature-score

Numerical differentiation for scores, Fisher informations