message: rm strictNullChecks
diff: "resolveJsonModule": true,
  "skipLibCheck": true,
  "forceConsistentCasingInFileNames": true,
  - "target": "ES2017",
  - "strictNullChecks": true
  + "target": "ES2017"
  + // "strictNullChecks": true
  },
  "include": ["src", "typings/*.d.ts"],
  "files": ["typings/global.d.ts"],
  