* Change `ping .. > nul` to `sleep`
The filename `nul` is a Windows-ism that causes the update script to
create such a file in the current working directory. The `ping`
utility is also an dependency not installed by
`installdependencies.sh`, so it seemed easier to change it to the
standard `sleep` command.
* Update dotnet-install script as requested by test
* Update dotnet-install.ps1
Co-authored-by: Tingluo Huang <tingluohuang@github.com>
* Unify apt/apt-get logic
The previous logic was buggy in that it tried to use `apt` in the `apt-get` branch after deciding that `apt` was unavailable...
* Prefer apt-get over apt
apt does not have a stable cli and using it from scripts yields annoying messages
* Improve English for missing apt-get & apt case
* Fix apt-get/apt fallback behavior for $ patterns
If there's a `$` in the apt install pattern, it will not fail if it selects a thing and decides it isn't interested in installing it.
* Fix spelling of libssl
