Keep the contributors table updated

[mkouba]

Please do not close this issue. It's used to add new contributors using the all-contributors bot.

[mkouba]

@all-contributors please add @jmartisk for doc.

[allcontributors]

@mkouba

I've put up a pull request to add @jmartisk! 🎉

[mkouba]

@all-contributors please add @iocanel for code.

[allcontributors]

@mkouba

I've put up a pull request to add @iocanel! 🎉

[mkouba]

@all-contributors please add @sberyozkin for example.

[allcontributors]

@mkouba

I've put up a pull request to add @sberyozkin! 🎉

[mkouba]

@all-contributors please add @kpavlov for test and infra

[allcontributors]

@mkouba

I've put up a pull request to add @kpavlov! 🎉

[mkouba]

@all-contributors please add @mvduijnhoven for code and test and doc