Refactor the code (#15)

* code refactoring

* Remove reference files

* Update README and CI

* small fixes

* fix style issues

* add style check for CI

* fix style issues

* remove kaldi-native-io

scripts/utils.sh

@@ -0,0 +1,19 @@
+#!/bin/bash
+
+default='\033[0m'
+bold='\033[1m'
+red='\033[31m'
+green='\033[32m'
+
+function ok() {
+  printf "${bold}${green}[OK]${default} $1\n"
+}
+
+function error() {
+  printf "${bold}${red}[FAILED]${default} $1\n"
+}
+
+function abort() {
+  printf "${bold}${red}[FAILED]${default} $1\n"
+  exit 1
+}