SETUP:  update ez_setup.py
SETUP/DOC:  egg-install
SETUP:  minimal dependency versions
ENH R:  Dataset.from_r() constructor
DOC R:  dependency
TEST:  compare ANOVA with R
ENH Dataset.aggregate():  add `never_drop` argument
ENH Model:  add ._effect_to_beta
OPT glm:  Cythonize LMFitter