Add emacs_select plugin

[kesslern]

Add plugin to provide emacs-like selection to Micro

[taconi]

Hello, could you update the PR to resolve the conflicts?

Another issue is that your repo.json does not have the Website and License fields, could you add this metadata?

Could you add your repo.json to the plugins/ folder and update channel.json link to use this link?
E.g. https://raw.githubusercontent.com/micro-editor/plugin-channel/master/plugins/editorconfig-micro.json.
Use the plugin name as the file name.