* feat: support custom key mapping
* remove testing code
* feat: support function key
* style: add comment
* feat: support read config
* docs: add keymap.yaml example
* docs: add function key in README
* refactor: rename config key name
* feat: support Alt prefix
* docs: fix syntax
* feat: let exit be configurable
* refactor: remove KeyEsc in keyNames
* refactor: space to Space
* refactor: style code
