feat: wrap license-check in promise

src/checker.js

@@ -0,0 +1,14 @@
+const checker = require('license-checker');
+
+const parsePackages = path => new Promise((resolve, reject) => {
+  checker.init({
+    start: path
+  }, (error, packages) => {
+    if (error) reject(new Error(`'license-checker error: ${error}`));
+    else resolve(packages);
+  });
+});
+
+module.exports = {
+  parsePackages
+};