Merge branch 'rs/strbuf-leakfix'

Many leaks of strbuf have been fixed.

* rs/strbuf-leakfix: (34 commits)
  wt-status: release strbuf after use in wt_longstatus_print_tracking()
  wt-status: release strbuf after use in read_rebase_todolist()
  vcs-svn: release strbuf after use in end_revision()
  utf8: release strbuf on error return in strbuf_utf8_replace()
  userdiff: release strbuf after use in userdiff_get_textconv()
  transport-helper: release strbuf after use in process_connect_service()
  sequencer: release strbuf after use in save_head()
  shortlog: release strbuf after use in insert_one_record()
  sha1_file: release strbuf on error return in index_path()
  send-pack: release strbuf on error return in send_pack()
  remote: release strbuf after use in set_url()
  remote: release strbuf after use in migrate_file()
  remote: release strbuf after use in read_remote_branches()
  refs: release strbuf on error return in write_pseudoref()
  notes: release strbuf after use in notes_copy_from_stdin()
  merge: release strbuf after use in write_merge_heads()
  merge: release strbuf after use in save_state()
  mailinfo: release strbuf on error return in handle_boundary()
  mailinfo: release strbuf after use in handle_from()
  help: release strbuf on error return in exec_woman_emacs()
  ...

diff --cc builtin/merge.c
Simple merge

diff --cc commit.c
Simple merge

diff --cc convert.c
Simple merge

diff --cc diff.c
Simple merge

diff --cc refs.c
Simple merge

diff --cc sha1_file.c
Simple merge

diff --cc transport-helper.c
Simple merge