[PATCH v2 00/10] Makefile: make generate-cmdlist.sh much faster

This version of this series drops the Makefile-powered version of the cmdlist in favor of making the shellscript much faster, mostly with suggestions from Jeff King.

I still think that splitting out the generated data into files may be useful for unifying the Documentation/ and C code build processes, there's another custom parser for command-list.txt in Documentation/cmd-list.perl.

But if and when I've got something for that I can dig that out of the v1, in the meantime the v1 of this should be mostly uncontroversial.

The last tow patches make things a bit slower for me, but since they replace command invocations with pure-shell logic they presumably make things a bit less painful on e.g. Windows, and the 8th patch here already made things quite very fast already.

Jeff King (1):
  generate-cmdlist.sh: do not shell out to "sed"

Johannes Sixt (2):
  generate-cmdlist.sh: spawn fewer processes
  generate-cmdlist.sh: replace for loop by printf's auto-repeat feature

Ævar Arnfjörð Bjarmason (7):
  command-list.txt: sort with "LC_ALL=C sort"
  generate-cmdlist.sh: trivial whitespace change
  generate-cmdlist.sh: don't call get_categories() from category_list()
  generate-cmdlist.sh: run "grep | sort", not "sort | grep"
  generate-cmdlist.sh: stop sorting category lines
  generate-cmdlist.sh: replace "grep' invocation with a shell version
  generate-cmdlist.sh: replace "cut", "tr" and "grep" with pure-shell

 command-list.txt    | 20 +++++++-------
 generate-cmdlist.sh | 66 ++++++++++++++++++++++++++-------------------
 2 files changed, 48 insertions(+), 38 deletions(-)

Range-diff against v1:
 1:  96885282988 =  1:  96885282988 command-list.txt: sort with "LC_ALL=C sort"
 2:  5e8fef90e42 =  2:  5e8fef90e42 generate-cmdlist.sh: trivial whitespace change
 3:  6b4de6a6088 =  3:  6b4de6a6088 generate-cmdlist.sh: spawn fewer processes
 4:  074685cf714 =  4:  074685cf714 generate-cmdlist.sh: don't call get_categories() from category_list()
 5:  f01c1fd8088 =  5:  f01c1fd8088 generate-cmdlist.sh: run "grep | sort", not "sort | grep"
 6:  e0b11514b8d =  6:  e0b11514b8d generate-cmdlist.sh: replace for loop by printf's auto-repeat feature
 7:  0c6f9b80d3b <  -:  ----------- Makefile: stop having command-list.h depend on a wildcard
 8:  23d4cc77b6c <  -:  ----------- Makefile: assert correct generate-cmdlist.sh output
 -:  ----------- >  7:  f2f37c2963b generate-cmdlist.sh: stop sorting category lines
 -:  ----------- >  8:  83318d6c0da generate-cmdlist.sh: do not shell out to "sed"
 -:  ----------- >  9:  7903dd1f8c2 generate-cmdlist.sh: replace "grep' invocation with a shell version
 -:  ----------- > 10:  e10a43756d1 generate-cmdlist.sh: replace "cut", "tr" and "grep" with pure-shell