fix memory leak by clearing interval on destroy hook
fix memory leak by clearing interval on destroy hook

martindale/bitcore,bitjson/bitcore,martindale/bitcore,bitjson/bitcore,bitpay/bitcore,martindale/bitcore,bitpay/bitcore,bitjson/bitcore,bitpay/bitcore,bitpay/bitcore,bitjson/bitcore,martindale/bitcore