DOC: Fixing symlinks killed in 31f24b19724efe9e506a374a3a8ad27c398cc3db
ENH: fixing up permissions -- do not set to executable whatever is not
DOC+ENH: Adding more to modref documentation + tuning up docstrings + adding __all__ to restrict public space of some submodules
DOC: searchlight_surf.py -- fixing up references and removing trailing spaces
DOC: svm_margin -- few empty lines for proper example2rst functioining
BF:  move import of statsmodels under if externals.exists

It should be that way so we could build documentation even in absense of statsmodels
(IIRC)
DOC: fixing up references so they build again (we use utf-8) + adding missing Emanuele"s
ENH: use system-wide numpydoc if available
DOC: a variety of little fixes all around (adding missing links, removing trailing whitespaces, typos, links, etc)