Broken link in README for example json config file

[coolaj86]

Note: For detailed example configuration see regtest/cluster.js

https://github.com/dashevo/dashcore-node/blob/master/docs/services/regtest/cluster.js

[coolaj86]

Perhaps this refers to https://github.com/dashevo/dashcore-node/blob/master/regtest/cluster.js?