[tests] Add wallet-tool test

Original tests by João Barbosa <joao.paulo.barbosa@gmail.com>

Additional contribution by John Newbery <john@johnnewbery.com>

test/functional/test_framework/test_framework.py

@@ -139,6 +139,7 @@ class BitcoinTestFramework(metaclass=BitcoinTestMetaClass):
 
         config = configparser.ConfigParser()
         config.read_file(open(self.options.configfile))
+        self.config = config
         self.options.bitcoind = os.getenv("BITCOIND", default=config["environment"]["BUILDDIR"] + '/src/bitcoind' + config["environment"]["EXEEXT"])
         self.options.bitcoincli = os.getenv("BITCOINCLI", default=config["environment"]["BUILDDIR"] + '/src/bitcoin-cli' + config["environment"]["EXEEXT"])