Prepare fix #270

[sdruskat]

This PR prepares to fix #270 for this repository.

Note: Do not merge, instead, follow "Fixing..." below.

Done:

• Replace relevant instances of master with main in content:
  • for F in $(ack -l master); do sed -i 's~master~main~g' $F; done
  • for F in $(ack -l master); do sed -i 's~de-rse.github.io/blob/master~de-rse.github.io/blob/main~g' $F; done
  • Manual check and replacement of de-rse.github.io/tree/master
• Manual check of replacement of false positives (ack master in repo root)

Fixing #270 (for this repo)

I think this is basically now:

• Set main branch as default
• See if page builds and deploys (assuming Action uses default branch)
• Remove/rename master branch

[chillenzer]

It is mildly confusing to have this as a PR from main into master, but I see where you're going with this.

[sdruskat]

It is mildly confusing to have this as a PR from main into master, but I see where you're going with this.

Ah, yes. Added a comment to this effect. Had relied on the presence of mine of the maintainers...