Merge branch 'js/filter'

Merge branch 'js/filter'

* js/filter:
  filter-branch: subdirectory filter needs --full-history
  filter-branch: Simplify parent computation.
  Teach filter-branch about subdirectory filtering
  filter-branch: also don't fail in map() if a commit cannot be mapped
  filter-branch: Use rev-list arguments to specify revision ranges.
  filter-branch: fix behaviour of '-k'
  filter-branch: use $(($i+1)) instead of $((i+1))
  chmod +x git-filter-branch.sh
  filter-branch: prevent filters from reading from stdin
  t7003: make test repeatable
  Add git-filter-branch