Merge branch 'jk/delete-modechange-conflict'

Merging a branch that removes a path and another that changes the
mode bits on the same path should have conflicted at the path, but
it didn't and silently favoured the removal.

* jk/delete-modechange-conflict:
merge: detect delete/modechange conflict
t6031: generalize for recursive and resolve strategies
t6031: move triple-rename test to t3030

diff --cc merge-recursive.c
Simple merge