Automatic reparsing of %sh{...}, while convenient in many cases,
can be surprising as well, and can lead to security problems:
'echo %sh{ printf "foo\necho bar" }' runs 'echo foo', then 'echo bar'.
we make this danger explicit, and we fix the 'nop %sh{...}' pattern.
To reparse %sh{...} strings, they can be passed to evaluate-commands,
which has been fixed to work in every cases where %sh{...} reparsing
was used..
- the file was edited with a different editor/program or
- kak didn't restore a backup or
- if old backups weren't purged or
- if autorestore wasn't loaded (e.g. `kak -n`) after backups were generated.
This commit allows buffers that were not previously written to disk to
be restored if a backup has been generated in their name. Consequently,
we got rid of a few non-POSIX calls to `find` (using `-maxdepth` or
`-delete`), and of the logic that detected the newest backup (which
didn't seem a good reason enough to steer away from a portable command).
Fixes#1236
