Merge branch 'en/fetch-negotiation-default-fix'

Interaction between fetch.negotiationAlgorithm and
feature.experimental configuration variables has been corrected.

* en/fetch-negotiation-default-fix:
  repo-settings: rename the traditional default fetch.negotiationAlgorithm
  repo-settings: fix error handling for unknown values
  repo-settings: fix checking for fetch.negotiationAlgorithm=default

diff --cc repo-settings.c
Simple merge

diff --cc repository.h
Simple merge

diff --cc t/t5500-fetch-pack.sh
Simple merge