Merge branch 'jn/fast-import-fix'

* jn/fast-import-fix:
  fast-import: do not clear notes in do_change_note_fanout()
  t9300 (fast-import): another test for the "replace root" feature
  fast-import: tighten M 040000 syntax
  fast-import: filemodify after M 040000 <tree> "" crashes

diff --cc fast-import.c
Simple merge

diff --cc t/t9300-fast-import.sh
Simple merge