Native Segwit & Multi-Coin Update

Updated from Gurnec's last Dec 2017 release.

*Now includes support for Legacy, Segwit and Native Segwit address types.
*Supports multiple 'bitcoin-like' cryptocurrencies for address based search
*Supports a number of 'bitcoin-like' blockchains for AddressDB Creation (BCH, LTC, VTC, Mona)
*Improved options for managing large blockchain and addressdb sizes both now and into the future (date based filtering, limiting blocks that are included, removing hardcoded limits on AddressDB size, etc)