Match maparg's return type.

These occurrences also accept string, which is used like in getline.

Also make the lnum field of vim.fn.sign_placelist.list.item optional, as it can
be omitted like vim.fn.sign_place.dict's.

Problem:  Strange error with type for matchfuzzy() "camelcase".
Solution: Show the error "Invalid value for argument camelcase" instead
          of "Invalid argument: camelcase" (zeertzjq).

Note that using tv_get_string() will lead to confusion, as when the
value cannot be converted to a string tv_get_string() will also give an
error about that, but "camelcase" takes a boolean, not a string.  Also
don't use tv_get_string() for the "limit" argument above.

closes: vim/vim#16926

https://github.com/vim/vim/commit/c4815c157b27923001e44bfd241fb540bf1fb518

Problem:  When searching for "Cur", CamelCase matches like "lCursor" score
          higher than exact prefix matches like Cursor, which is
          counter-intuitive (Maxim Kim).
Solution: Add a 'camelcase' option to matchfuzzy() that lets users disable
          CamelCase bonuses when needed, making prefix matches rank higher.
          (glepnir)

fixes: vim/vim#16504
closes: vim/vim#16797

https://github.com/vim/vim/commit/28e40a7b55ce471656cccc2260c11a29d5da447e

Co-authored-by: glepnir <glephunter@gmail.com>

Co-authored-by: Au. <acehinnnqru@gmail.com>
Co-authored-by: Daniel Rainer <daniel.rainer@localhost>
Co-authored-by: Evgeni Chasnovski <evgeni.chasnovski@gmail.com>
Co-authored-by: Lewis Russell <lewis6991@gmail.com>
Co-authored-by: Luuk van Baal <luukvbaal@gmail.com>
Co-authored-by: Pierre Barbin <pierre@heitzsystem.com>
Co-authored-by: Riley Bruins <ribru17@hotmail.com>
Co-authored-by: Yinzuo Jiang <jiangyinzuo@foxmail.com>
Co-authored-by: phanium <91544758+phanen@users.noreply.github.com>
Co-authored-by: zeertzjq <zeertzjq@outlook.com>

"umask" is pronounce like "youmask", so having an "an" before it is a
bit strange.  In other places in the help, "umask" is not preceded by
either "a" or "an", and sometimes preceded by "the".

Also, "Note" is usually followed either by ":" or "that" in builtin.txt,
so add a ":" after "Note".

closes: 16860

https://github.com/vim/vim/commit/c1c3b5d6a0a3032057bf6de8672cc79100bb73c9

fixes: vim/vim#16849

https://github.com/vim/vim/commit/0a336ccb57003c44ba303ccc50cf50cb640c2309

Co-authored-by: Christian Brabandt <cb@256bit.org>

related: vim/vim#16607

https://github.com/vim/vim/commit/5647c91355f1ff3a1030c737bf5133bb7da5bb76

Co-authored-by: Christian Brabandt <cb@256bit.org>