config/config library

1. t_chain_payment_sdk package
2. documentation
3. config/config.dart

t_chain_payment_sdk package

1. Libraries
2. config/config
3. data/t_chain_payment_action
4. data/t_chain_payment_currency
5. data/t_chain_payment_env
6. data/t_chain_payment_qr_result
7. data/t_chain_payment_result
8. t_chain_payment_sdk