Merge branch 'jc/read-tree'

* jc/read-tree:
t6022: ignoring untracked files by merge-recursive when they do not matter
merge-recursive: adjust to loosened "working file clobbered" check
merge-recursive: make a few functions static.
merge-recursive: use abbreviated commit object name.
merge: loosen overcautious "working file will be lost" check.

diff --cc merge-recursive.c
Simple merge