Merge branch 'jk/peel-ref'

Recent optimization broke shallow clones.

* jk/peel-ref:
  upload-pack: load non-tip "want" objects from disk
  upload-pack: make sure "want" objects are parsed
  upload-pack: drop lookup-before-parse optimization

diff --cc t/t5500-fetch-pack.sh
Simple merge

diff --cc upload-pack.c
Simple merge