Order authors

[mhagdorn]

I have modified the contributors processing script to order the authors by last name and move the corresponding author (@dokempf) to the front

[CaptainSifff]

Abusing this PR: in #35 We have Uwe Schmitt as contributor.

[dokempf]

@mhagdorn Thanks for looking into this. In fact, we do have multiple tiers of authorship (the core team is mentioned first). In order to implement this, I went an alternative implementation route (annotating contribution tier in YAML) in #110.