Merge branch 'topic/wysh'
* topic/wysh:
nail.1: add note to quote ; and | (hopefully we get there!)
Drop list.c, add new cmd_arg.c..
n_shell_quote(): rewrite, tweak user-at-a-glance experience
MLE: change HT expansion..
Drop wordexp(3), instead unroll via fnmatch(3)..
Localize n_shell_expand_tilde() and n_shell_expand_var()..
Add n_shell_parse_token_buf() wrapper
n_shell_quote*(): add a "roundtrip" argument
Add n_visual_info(), drop field_detect_width()
n_shell_parse_token(): correct handling of comments
Sprinkle #ifdef HAVE_NATCH_CHAR; ensure \x/\u doesn't clash data..
Add n_iconv_onetime_cp()..
`remove': use sh(1)ell-style quoting
Drop fexpand_nshell_quote(), all users go for sh(1)ell-style
(BWDIC!) Only use new sh(1)-style quoting for `write'
Remove n_shell_sep() again, instead _pimp_ n_shell_parse_token()!
Remove n_strescsep() again..
(BWDIC!) Only use new sh(1)-style quoting for attachments!
(TMP) Add n_shell_sep(), a better successor of strsep()
(TMP) wordexp(3) or nothing, no longer use 'echo %s' for expansions..
Add FEXP_NVAR (do not even expand $VAR)
`customhdr': disallow using control characters in bodies
Add PS_WYSHLIST_SAW_CONTROL and auto-check for control characters
Only support sh(1)-style quoting for some new commands..
Support `wysh' keyword prefix, here and there
Introduce `wysh' command prefix to change argument parser..