Add device crd, mapper, mapper-framework docs

[wbc6080]

• Please check if the PR fulfills these requirements

• [x] The commit message follows our guidelines
• [x] Tests for the changes have been added (for bug fixes / features)
• [x] Docs have been added / updated (for bug fixes / features)

• What kind of change does this PR introduce? (Bug fix, feature, docs update, ...) update dmi and mapper-framework docs, introduce v1beta1 device API

[cl2017]

/lgtm

[WillardHu]

/lgtm

[wbc6080]

cc @Shelley-BaoYue @fisherxu thanks

[kubeedge-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: fisherxu

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• ~~OWNERS~~ [fisherxu]

Approvers can indicate their approval by writing /approve in a comment Approvers can cancel approval by writing /approve cancel in a comment