Add SGD Regression widget.
SGD regression add linear.py.
SGDRegression test.
Use base model 'data' implementation for non Variable items.
Added Hierarchical Clustering widget.
Added hierarchical clustering icon.
Removed unused code.
SGDRegression parameters pack.
Merge branch 'master' into hierarchical-clustering
Merge pull request #148 from acopar/master

Add SGD regression widget
Changed input/output type declarations to DistMatrix.
Clean and PEP8 classification tree viewer
Simplify size and edge settings in classification tree viewer
Simplify coloring in classication tree viewer
Simplify node info
Simplify pies in classification tree viewer
Further cosmetics on tree viewer
Context settings and much nicer design for tree viewer
Print conditions in trees with proper number of decimals
Moved hierarchical clustering functions...

... under Orange.clustering.hierarchical namespace.