Merge branch 'tc/last-modified-bloom' into seen

Merge branch 'tc/last-modified-bloom' into seen

The 'git last-modified' command has been optimized by using Bloom
filters.  It now reuses revision walk filtering logic from 'git log'
to pre-filter commits, and maintains per-path Bloom filters even when
wildcard pathspecs are used.

* tc/last-modified-bloom:
  last-modified: keep per-path Bloom filters for wildcard pathspecs
  last-modified: check pathspec against Bloom filter first
  revision: expose check for paths maybe changed in Bloom filter
  revision: move bloom keyvec precondition into function