Merge branch 'sb/diff-blobfind-pickaxe'

"diff" family of commands learned "--find-object=<object-id>" option to limit the findings to changes that involve the named object. * sb/diff-blobfind-pickaxe: diff: use HAS_MULTI_BITS instead of counting bits manually diff: properly error out when combining multiple pickaxe options diffcore: add a pickaxe option to find a specific blob diff: introduce DIFF_PICKAXE_KINDS_MASK diff: migrate diff_flags.pickaxe_ignore_case to a pickaxe_opts bit diff.h: make pickaxe_opts an unsigned bit field