0.2.0

Added:

• Add base.which, base.bessel, base.special, base.trig_hb and base.string modules
• Add Support for duplicated keyword arguments for dplyr.mutate/summarise by using _ as suffix
• Warn when import python builtin names directly; ; Remove modkit dependency

Fixed:

• Fixed errors when usea_1 as names for "check_unique" name repairs
• Fixed #14: f.a.mean() not applied to grouped data

Changed:

• Don't allow from datar.datasets import *
• Remove modkit dependency
• Reset NaN to NA
• Rename base.getOption to base.get_option
• Rename stats.setNames to stats.set_names