[docs] [issue27635] pickle documentation says that unpickling may not call __new__

Changes by Serhiy Storchaka <storchaka+cpython@gmail.com>: ---------- nosy: +alexandre.vassalotti, serhiy.storchaka stage: -> needs patch type: -> behavior versions: +Python 3.7 -Python 3.4 _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue27635> _______________________________________