Add a dedicated sharing image for Pixi.

[matthiasrohmer]

[patrickkettner]

@matthiasrohmer could you elaborate? never mind, I remembered what this was about

[patrickkettner]

@sebastianbenz would it make sense to have ferdi or some one design a shared image that could be generated to show off peoples scores?

[sebastianbenz]

That'd be cool. Although I think having two versions (OK, NOK) would be sufficient. The absolute scores are less interesting.

[patrickkettner]

ferdi created some general sharing images

I requested version that are "pass" or "fail" in addition to that, ideally with a score and/or url