Dali-rp2

* added new RP2 Input data loader plugin, which can read RP2 input format data back into DaLI
* improvements to Kraken CSV pair converter plugin: price data files are now downloaded locally and chunked to avoid excessive memory use
* improvements to Coinbase plugin: added support for advanced_trade_fill, cardspend and cardbuyback
* various smaller fixes and improvements

* added CCXT pair converter subclasses that are fixed to one exchange (Kraken, Binance)
* added fiat deposit support to Bitbank plugin
* small fixes and improvements

* added Kraken CSV price importer
* various fixes to CCXT-based plugins
* small improvements to some CSV data loaders
* updated documentation

* added CCXT-based abstract superclass for REST data loader plugins (80): this makes it much easier to add a new REST-based data loader
* added Bitbank REST input plugin and CSV supplemental input plugin
* added Coincheck CSV supplemental input plugin
* updated RP2 to 1.3.1
* updated documentation

* As of RP2 1.3.0, RP2 configuration files are no longer expressed in JSON format: they now use the INI format. So DaLI has been updated to generates INI-format configuration files instead of JSON. Any old JSON-format configuration file can be converted to the new INI format with the following command: rp2_config <json_config>
* added Pionex CSV data loader plugin

* added Binance.com REST data loader plugin
* added Binance.com supplemental (CSV) data loader plugin (for autoinvest purchases and ETH to BETH conversions)
* added CCXT-based pair converter
* updated documentation