Merge branch 'kn/reftable-consistency-checks' into jch

The reftable backend learned to sanity check its on-disk data more
carefully.

Comments?

* kn/reftable-consistency-checks:
  refs/reftable: add fsck check for checking the table name
  reftable: add code to facilitate consistency checks
  fsck: order 'fsck_msg_type' alphabetically
  Documentation/fsck-msgids: remove duplicate msg id
  reftable: check for trailing newline in 'tables.list'
  refs: move consistency check msg to generic layer
  refs: remove unused headers

diff --cc Makefile
Simple merge

diff --cc meson.build
Simple merge

diff --cc refs.c
Simple merge

diff --cc refs/debug.c
Simple merge

diff --cc refs/files-backend.c
Simple merge

diff --cc refs/reftable-backend.c
Simple merge

diff --cc reftable/stack.c
Simple merge

diff --cc t/meson.build
Simple merge