`LANGUAGE=C` is not enough, `LC_ALL=C` is needed as the environment
variable that overrides all the other localization settings.
e.g.
```bash
$ LANGUAGE=C id foobar
id: ‘foobar’: no such user
$ LC_ALL=C id foobar
id: 'foobar': no such user
```
* replace `LANGUAGE` with `LC_ALL` as environment variable in the tests
* fix the the date string of affected uutils
* replace `‘` and `’` with `'`
Calling `cmd_keepenv("mv")` spawned the system `mv` instead of
the uutils `mv`. Also, `keepenv` isn't necessary because it doesn't
need to inherit environment variables.
We now actually check the stderr, because previously the result of
`ends_with` was not used, making the test pass even when it shouldn't.
I disabled the test on windows because `mkdir` does not support `-m` on
windows, making the test fail because there will be no permission error.
On FreeBSD there isn't a permission error either, and `mv` succeeds.
Data that was previously boxed inside the `Line` struct was moved to
separate vectors. Inside of each `Line` remains only an index that
allows to access that data.
This helps with keeping the `Line` struct small and therefore reduces
memory usage in most cases.
Additionally, this improves performance because one big allocation (the
vectors) are faster than many small ones (many boxes inside of each
`Line`). Those vectors can be reused as well, reducing the amount of
(de-)allocations.
On some Windows machines this would otherwise cause `std::env::temp_dir`
to fall back to a path that is not writeable (C:\\Windows).
Since by default integration tests don't inherit env vars from the
parent, we have to override this in some cases.
- Windows hidden file attribute determination would assume symbolic link
to be valid and would panic
- Check symbolic link's attributes if the link points to non-existing
file
- For dangling symlinks, errors should only be reported if
dereferencing options were passed and dereferencing was applicable to
the particular symlink
- With -i parameter, report '?' as the inode number for dangling
symlinks
When invoked via '[' name, last argument must be ']' or we bail out with
syntax error. Then the trailing ']' is simply disregarded and processing
happens like usual.
