Merge branch 'tb/print-size-t-with-uintmax-format'

Code preparation to replace ulong vars with size_t vars where
appropriate.

* tb/print-size-t-with-uintmax-format:
Upcast size_t variables to uintmax_t when printing

diff --cc builtin/cat-file.c
Simple merge

diff --cc builtin/index-pack.c
Simple merge

diff --cc builtin/pack-objects.c
Simple merge

diff --cc diff.c
Simple merge

diff --cc ref-filter.c
Simple merge

diff --cc sha1-file.c
Simple merge