Merge branch 'ps/doc-packfile-vs-pack-file' into maint

Doc consistency updates. * ps/doc-packfile-vs-pack-file: doc: fix inconsistent spelling of "packfile" pack-protocol.txt: fix insconsistent spelling of "packfile" git-unpack-objects.txt: fix inconsistent spelling of "packfile" git-verify-pack.txt: fix inconsistent spelling of "packfile"