add example,readme and gitignore file

Author: kakzhou719

.gitignore

@@ -13,12 +13,4 @@ _output
 .idea
 seautil/seautil
 sealer/sealer
-*.swp
-
-pkg/cloud/dashboard/target/
-pkg/cloud/dashboard/dist/
-pkg/cloud/dashboard/Cargo.lock
-
-docs/site/node_modules
-docs/site/package-lock.json
-
+*.swp