Support indeterminate state in checkbox component through props

[zillding]

Prerequisites

• I have searched for duplicate or closed feature requests
• I have read the contributing guidelines

Proposal

Support indeterminate state in checkbox component through a new prop like indeterminate or extending existing prop like checked

Motivation and context

This is to make usage of indeterminate checkbox easier in the react context without the need to manually manipulate DOM object through JS.

[clukhei]

Could you describe your use case for indeterminate checkbox? @zillding