v0.12.0

• Add dataframe.GetGroups (@arjunmahishi)
• Fix dataframe.GroupBy issue (@prliu)
• Add Series.Slice (@jfussion)
• Add csv lazy quote (@fredericlemoine)
• making series Order stable (@mcolosimo-p4)
• fix linter issues (@chrmang)

v0.11.0

Release 0.11.0