Review on dataframe serializer
upon team agreement:
- remove V3 & alpha V2 support JSON 'columns' format on write bulk APIs
- JSON 'columns' still supported on V3 & alpha V2 on read bulk APIs
- on legacy V2 read/write bulk APIs, supports unchanged but no convert axes from Pandas.
- no try to infer date time type from JSON. This was already the case on V3 & alpha V2. This change impacts only legacy V2 but mainly fix unwanted index & column alteration. Date time passed using JSON will pass stored as-it in plain string. Parquet format must be used for full typed date time index.