Fix labels of inliers vs outliers

At least based on what svm.OneClassSVM does in the example linked from this document, the description was wrong; labels actually assigned are 1/-1 for good/bad respectively, not 0/1.
Cosmetic: correct latex formula display
DOC: write cost function of logistic regression.

I feel it important to state clearly what is the cost function of the
model because:

    * Some might want to compare their implementation against this one,
    in which case it is important to know exactly what is the form of the
    cost function

    * Furthermore since the models are quite inconsistent in terms of
    notation for the regularization parameter: some models in this
    module penalize by 1/C, others by alpha and others by alpha/2
Merge pull request #3365 from fabianp/master

DOC: write cost function of logistic regression
Link my name to my wordpress blog
Merge pull request #3366 from MechCoder/link-to-blog

FIX: My name was linked to the wrong github account
fixed typo: diriclet -> dirichlet
Merge pull request #3368 from stevetjoa/typo-diriclet

fixed typo: diriclet -> dirichlet
DOC updated installation documentation

Added Canopy and Anaconda.
Removed EPD.
Merge pull request #3369 from NelleV/install_doc

DOC updated installation documentation
DOC: typo, envelop → envelope
Merge branch 'pr/3358'
MAINT Re-order argument to put deprecated one at the end
DOC: add transpose and intercept to formula of logistic regression
MAINT configure Windows CI with appveyor.com