DOC metrics and hierarchical clustering
BUG: ward does not take an affinity
changing test
DOC: example metric + hierarchical clustering

Still a work in progress
WIP example l1 metrics hierarchical cluster
saving the random state
Merge branch 'master' into hc_linkage

Conflicts:
	sklearn/cluster/tests/test_hierarchical.py
BUG: different distance names in scipy
BUG: fix minor floating-point precision detail
ENH: Py3 support
BUG: fix tests under Python 3

DeprecationWarning is skipped by default in Python 3
DOC: improve the clustering metric example
making adjustments to variable names and account for sparse matrices
changing xrange to range
DOC: AgglomerationClustering doc and examples
DOC: Agglomeration clustering docs and examples
DOC: connectivity in agglomerative clustering

Explain the percolation effect.
DOC: finish touches to hierarchical docs
MISC: typos in docs
MISC: remove reference to deprecated Ward