FIX: random_start feature in GaussianProcess
FIX: gp_diabetes_dataset examples (theta_ attribute)
DOC link example gallery scripts rather than inline
COSMIT
DOC show referring examples on API reference pages
DOC ensure longer underline
TST: fix tests on numpy 1.9.b2
Refactor input validation.
Merge pull request #3443 from amueller/input_validation_refactoring

[MRG] Input validation refactoring
remove check_arrays stuff and old input validation
ENH add allowed_sparse named argument for @ogrisel
Merge pull request #3447 from amueller/input_validation_b

[WIP] remove check_arrays stuff and old input validation
FIX classes name in OvR
DOC mention doc-building dependency on Pillow
Merge pull request #3327 from jnothman/examples_in_apiref

DOC show referring examples on API reference pages
DOC make neural networks example appear

Also make the absence of a README fail doc compilation
DOC Fix example path
DOC fix 'Return' -> 'Returns'
FIX Py3k support for out-of-core example
DOC add links to github sourcecode in API reference