Bug 1090843 - Improve the time required for being interactive

- Delay load the modules for loading hardware information required in the module of the root panel.
- Delay the use of query selectors in the init function of the root panel.
- Remove redundant setTimeouts in the panel navigation process.
- Some modules required in main.js are delay loaded.
I noticed that in this file, we have so many `'use strict'`, should we just extract them into one ?