Margin tables (#45)

* add isolated tables

* add Table description

* adapt BinanceDataBase trade methods to isolated margin

* adapt BinanceManager to isolated margin trades

* Add update method for all isolated margin trades

* adapt margin repays for isolated asset

* add get_margin_symbol_info for BinanceMananger (isolated and cross)

* correct isolated margin repays update

* add isolated margin repays update

* add isolated margin interests update

* add isolated margin transfers

* optimize isolated margin update

* update README and docs