Circumvent alternative Python implementations using dict for __builtins__
update word2vec docs
update minimum required version of `six`
* as per bug report https://groups.google.com/forum/#!topic/gensim/AjG58h9zBGg
fix ImportError with six 1.2.0
Merge pull request #259 from larsmans/six-importerror

fix ImportError with six 1.2.0
Merge pull request #260 from piskvorky/builtins_fix

Circumvent alternative Python implementations using dict for __builtins_...
Merge branch 'phrases' of https://github.com/mfcabrera/gensim into mfcabrera-phrases
make Phrases a transformation, doc update, py3k & unicode fixes
* bigram[doc] and bigram[corpus] now both work, and the latter returns an iterable (not just a generator)
* made a cross reference from word2vec to phrases, so people find the module
* return unicode consistently, but accept both utf8 and unicode on input
update changelog with merged PRs
py3k str fix
add pruning test & improve logging & py3k fix
change Phrases wording from "document" => "sentence"
increase default max vocab size to 40m (was: 20m)
make the phrase scoring formula explicit
make the bigram delimiter tweakable (default: `_`)
Merge pull request #1 from piskvorky/mfcabrera-phrases

Fixes to phrases PR