Dump of backlogged commits coming

[Bart Schaefer <schaefer@xxxxxxxxxxxxxxxx>]

I finally had several daylight hours with nothing else to do, so here
come 12 commits for patches that I either wrote or indicated that I
would commit on behalf of others (plus a 13th from Marlon that just
came in today).

Here's the ChangeLog entry:

2021-09-06  Bart Schaefer  <schaefer@xxxxxxx>

        * Stephane Chazelas: 45180: Doc/Zsh/contrib.yo,
        Functions/Example/zpgrep, Functions/Misc/regexp-replace: clarify
        doc for POSIX EREs, fix an issue with PCRE when the replacement
        was empty or generated more than one element

        * zeurkous: 49154: Doc/Zsh/exec.yo: clarify status on exec failure

        * Marlon Richert: 49378: Src/parse.c: skip check for collision
        of aliases and functions when NO_EXEC

        * Marlon Richert: 49292: Src/Zle/complist.c: turn off colors
        before clearing to end of line

        * 49282: set $0 correctly when calling functions from hooks

        * 49266: fix segfault on metacharacters in long job texts

        * Marlon Richert: 49218: Functions/Misc/run-help,
        Functions/Misc/run-help-btrfs, Functions/Misc/run-help-git,
        Functions/Misc/run-help-ip, Functions/Misc/run-help-p4,
        Functions/Misc/run-help-svk, Functions/Misc/run-help-svn:
        run-help filters cmd_args before calling run-help-<command>

        * unposted (cf. 49202 and 49217): Src/Zle/zle_hist.c: insertlastword
        ignores blank/missing history entries when repeating

        * 49196: Src/Modules/db_gdbm.c: gdbm keys not present in the
        database appear unset in tied hashes

        * Marlon Richert: 48969: fix for "zle -N" completion

        * 48888: Doc/Zsh/mod_system.yo, Doc/Zsh/params.yo, Test/E03posix.ztst:
        improve doc for $$ and $PPID, add fail test for PPID readonly-ness

        * 48832: Completion/Unix/Type/_urls: try _gnu_generic first