[WIP PATCH 00/22] Some updates since v3

Most commit messages issues get fixed in this series. The parent rewriting is still in progress and now part of it can be used very well to prune out uninteresting merges. The '--always-print' option is changed to '--full-line-diff', this option can be used by users to get a more detail line evovlment info. And the senmatic of this option will be changed later in the real v4 version of this series. Notice that, this series will break one of test because of '--full-line-diff' refactoring, just ignore it. :)

Bo Yang (22):
  parse-options: enhance STOP_AT_NON_OPTION
  parse-options: add two helper functions
  Add the basic data structure for line level history
  Refactor parse_loc
  Parse the -L options
  Export three functions from diff.c
  Add range clone functions
  map/take range to the parent of commits
  Print the line log
  Hook line history into cmd_log, ensuring a topo-ordered walk
  Add --full-line-diff option
  Add tests for line history browser
  Document line history browser
  Make rewrite_parents public to other part of git
  Add parent rewriting to line history browser
  Add --graph prefix before line history output
  Add test cases for '--graph' of line level log
  a fast fix
  Make graph_next_line external to other part of git
  some changes
  commit parents prunning code
  A merge should not be printed anyway

 Documentation/blame-options.txt     |   19 +-
 Documentation/git-log.txt           |   17 +
 Documentation/line-range-format.txt |   18 +
 Makefile                            |    2 +
 builtin/blame.c                     |   89 +--
 builtin/log.c                       |  111 +++-
 diff.c                              |    6 +-
 diff.h                              |   17 +
 diffcore.h                          |    1 +
 graph.c                             |   14 +-
 graph.h                             |   10 +
 line.c                              | 1542 +++++++++++++++++++++++++++++++++++
 line.h                              |  141 ++++
 parse-options.c                     |   22 +-
 parse-options.h                     |    7 +-
 revision.c                          |   22 +-
 revision.h                          |   22 +-
 t/t4301-log-line-single-history.sh  |  567 +++++++++++++
 t/t4302-log-line-merge-history.sh   |  163 ++++
 19 files changed, 2661 insertions(+), 129 deletions(-)
 create mode 100644 Documentation/line-range-format.txt
 create mode 100644 line.c
 create mode 100644 line.h
 create mode 100755 t/t4301-log-line-single-history.sh
 create mode 100755 t/t4302-log-line-merge-history.sh