Improve cli documentation

- Changes to documentation to make it more concise
- Improve installation steps documentation
- Surface available commands and mostly used options
  
```
$ origami-build-tools
```
Now outputs:

```
Usage: origami-build-tools <command> [<options>]

Commands:
   install  Install system and local dependencies
   build    Build module in current directory
   demo     Build demos into the demos/ directory
   verify   Lint code and verify if module structure follows the Origami specification
   test     Test if Sass silent compilation follows the Origami specification
   docs     Build module documentation into the docs/ directory

Mostly used options include:
   [--watch]                    Re-run every time a file changes
   [--local]                    Build demos locally, and preview them in a browser
   [--updateorigami]            Update origami.json with the latest demo files created
   [--js=<path>]                Main JavaScript file (default: ./src/main.js)
   [--sass=<path>]              Main Sass file (default: ./src/main.scss)
   [--buildJs=<file>]           Compiled JavaScript file (default: main.js)
   [--buildCss=<file>]          Compiled CSS file (default: main.css)
   [--buildFolder=<dir>]        Compiled assets directory (default: ./build/)
   [--scssLintPath=<path>]      Custom scss-lint configuration
   [--jsHintPath=<path>]        Custom JS Hint configuration
   [--editorconfigPath=<path>]  Custom .editorconfig

Full documentation: http://git.io/bBjMNw
```
We would rather keep the previous log. Actually, before, it was exactly, if not, very similar to your change, but it doesn't actually modify the config file, it runs the demos with a modified one, but doesn't overwrite the config file