add iriscli config docs

Author: MrXJC

docs/cli-client/README.md

@@ -55,3 +55,7 @@ Each modules provides a set of command line interfaces. Here we sort these comma
 9. [status command](./status/README.md)
 10. [tendermint command](./tendermint/README.md)
 11. [upgrade command](./upgrade/README.md)
+
+## iriscli config command
+
+The `iriscli config` command interactively configures some default parameters, such as chain-id, home, fee, and node.

docs/zh/cli-client/README.md

@@ -54,3 +54,7 @@
 9. [status command](./status/README.md)
 10. [tendermint command](./tendermint/README.md)
 11. [upgrade command](./upgrade/README.md)
+
+## iriscli config命令
+
+iriscli config命令可以交互式地配置一些默认参数，例如chain-id，home，fee 和 node。