Make cz-commitlint searchable and easy to get start

[curly210102]

Description

Update package.json and README.md of cz-commitlint package

1. add keywords of package.json
2. simplify README, only introduce important points
3. official document: provide a better screenshot and add "reference prompt" entry to sidebar

Motivation and Context

User can find "cz-commitlint" by keyword search.
Users can use it under clear instructions.

Usage examples

How Has This Been Tested?

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

[escapedcat]

Sometimes the circleci report doesn't work. We don't know why.
In circleci everything seems to look fine:

@curly210102 you have any idea? Otherwise I'll just merge this.

[curly210102]

@escapedcat I have no idea, try to rerun?

[escapedcat]

Can not find it here:
https://app.circleci.com/pipelines/github/conventional-changelog/commitlint

Only in yours:
https://app.circleci.com/pipelines/github/curly210102/commitlint/28/workflows/78f38403-1161-405f-8d3d-a4c2c96b4b82
And these are green.
On yours I'm not allowed to rerun checks:

You wanna click that and we'll see?

[curly210102]

@escapedcat aha, it's the ci of my forked project, unfollowed it now.

[escapedcat]

YAY!