- Add documentation for serving local files and embedded folders in README.md
- Add new example code for serving embedded folders in Go
- Create new `embed_folder.go` file with functions to serve embedded folders
- Create new `embed_folder_test.go` file with tests for serving embedded folders
- Add HTML template files for embedded server example
- Rename `static.go` to `local_file.go` and remove unused code
- Create new `local_file_test.go` file with tests for serving local files
- Create new `serve.go` file with middleware handler for serving static files
- Rename `static_test.go` to `serve_test.go` and refactor test functions
- Remove redundant test case `TestListIndex` from `serve_test.go`
Signed-off-by: Bo-Yi Wu <appleboy.tw@gmail.com>