ksh 93u+m/1.0.4

Main changes between 1.0.3 and 1.0.4:

• Fixed multiple scoping-related bugs in the += additive assignment operator.
• A number of crashing bugs have been fixed.
• Various fixes for the Haiku operating system, notably ulimit -a now works.
• Fixed the expansion of out-of-range \n back references in the string part of ${parameter//pattern/string}. For example:
  v=AB; echo "${v/@(A)B/\0:\1:\2}"
  now yields AB:A: instead of AB:A:\2.
• Fixed quoted !, ^ and - within [bracket] expressions in glob patterns; single or double quotes failed to disable their operator behaviour.
• Fixed a bug introduced on 2021-04-04 that incorrectly allowed typeset to turn off the readonly and export attributes on a readonly variable.
• In the emacs line editor, the Ctrl+R reverse-search prompt is now visually distinct from a literal control character (^R: instead of ^R).
• In the vi line editor, fixed the behaviour of C, c$ and I to be consistent with standard vi(1) and with Bolsky & Korn (1995, p. 121).
• Aliases for many GNU long options have been added to the /opt/ast/bin built-in commands. Additionally, kill -s now has a --signal long option alias compatible with the util-linux option.
• Backported support for print -u p from ksh 93v- for compatibility with scripts written for 93v-/ksh2020 (this is equivalent to 'print -p').

Full Changelog: v1.0.3...v1.0.4