add Zenodo DOI Badge

[SaulLu]

Proposal to add the Zenodo DOI Badge in the README.

The DOI used here corresponds to the Concept DOI (versus the Version DOIs), which represents the concept of the software package and all the versions of the given software package.

Currently, the Concept DOI links to the landing page for the latest version of our package. Note that in the future Zenodo plans to change this to create a landing page specifically representing the concept behind the record and all its versions.

[thomwolf]

You can addd citations informations in the README at the bottom of the readme as well

[SaulLu]

With pleasure!

We would like to put the link to the Concept DOI or the Version DOI (specific to the release v0.10.3)?

In the case of the Concept DOI, its last citation is not automatically populated on Zenodo. Would my proposal below be suitable?

@misc{hftokenizers2019,
  author = {Anthony MOI and
                  Pierric Cistac and
                  Nicolas Patry and
                  Evan P. Walsh and
                  Funtowicz Morgan and
                  Sebastian Pütz and
                  Thomas Wolf and
                  Sylvain Gugger and
                  Clément Delangue and
                  Julien Chaumond and
                  Lysandre Debut and
                  Patrick von Platen},
  title = {Hugging Face Tokenizers library},
  year = {2019},
  publisher = {GitHub},
  journal = {GitHub repository},
  doi = {10.5281/zenodo.4784271},
  howpublished = {\url{https://github.com/huggingface/tokenizers}}
}

[n1t0]

Looks good to me, but I'm no expert (maybe @thomwolf knows better). Feel free to add it to the readme, and we'll merge this :slightly_smiling_face: