ENH: use lgamma function from John D. Cook

Conflicts:
	sklearn/metrics/cluster/expected_mutual_info_fast.c
	sklearn/utils/lgamma.cpp
	sklearn/utils/lgamma.pyx
	sklearn/utils/setup.py
Merge branch 'master' into lgamma_port

Conflicts:
	sklearn/metrics/cluster/expected_mutual_info_fast.pyx
Merge pull request #1592 from jaquesgrobler/master

Remove warnings from example
P3K: division should produce integer.

Division using / produces a float under Python 3.x; it leads to
DeprecationWarnings because these float "n_features" makes "starts"
array float and values from "starts" are used as slice indices.
P3K: Fixed print related Python3 errors
P3K: avoid iteritems / itervalues when feasible
P3K: decode error message in svm wrapper
DOC : missing alpha doc in LassoLars
DOC cosmit fix column span alignment errors.
FIX example uses old parameter name
COMPatibility more careful deprecation of mode and k in SpectralClustering
COMP more careful deprecation of seed in SGDClassifier
COMP add deprecated property rho to ElasticNet
COMP keep seed as init parameter of Perceptron, only deprecate
COMP add deprecated ``labels_`` property to LinearSVC
FIX deprecated properties in ElasticNet
COMP in SVC rename self.label_ to self._label (it is redunant now but I don't want to refactor the rest of the day) and add a deprecated property label_, that points to classes_.
FIX in Perceptron and doctest
FIX in common tests: don't test init parameters that are deprecated. They might be changed.
FIX some doctests for SGD