Move sharpen to sampling part of controls.
Show more durations in sampling options.
Option to cache samples.
Prefix sample tables with underscores.
Fine tune sample times.
Extract get_domain method.
Ask for confirmation when guessing domain for a large table.
Merge pull request #147 from astaric/tune-heatmap

Tune heatmap
Fix missing parameter.
Added new distance metric and updated Orange Distances widget.

Included are cosine, manhattan and Jaccard distance metrics. All distances were updated to pass numpy objects to sklearn or scipy. Distances widget was updated to show all metrics. Tests for all distance metrics are now included.

Conflicts:
	Orange/tests/test_distances.py