Update README (translation progress)

[atsuyaw]

Update for the badges of the progress status in translation

[Cimbali]

Thanks for the update! The list of translators is auto-generated, if you prefer atsuyaw to Watanabe, would you mind renaming your name in the poeditor profile?

Also I’m thinking of dropping the github links as they don’t make a lot of sense anyways. (Note that your account will appear in the commit list anyways.)

[atsuyaw]

I added progress indicators for some languages because I thought they might activate contributions.
Editing the list was not the main aim, but thank you 😄