1. Use `log::info` to print some informantion which we would want to
display in release mode,
2. Add config to switch back `debug` log level in development mode.
related: #688 .
There are some unfinished things that need to be finalised by Boshen.
1. Official icon and description for the package.
2. Publishing strategy ( It's probably not a good idea to use
`package.json` as a probe to publish extension, as there's too much
vscode configuration coupled to it, a git tag like `vscode_v0.0.x` might
be worth considering ).
3. License for the extension.
