chore(docs): add description and kewords
chore(docs): add description and kewords

RxJS-CN/RxJS-Docs-CN,RxJS-CN/RxJS-Docs-CN,SangKa/RxJS-Docs-CN,SangKa/RxJS-Docs-CN,RxJS-CN/RxJS-Docs-CN,SangKa/RxJS-Docs-CN,SangKa/RxJS-Docs-CN,RxJS-CN/RxJS-Docs-CN