This brings chef-shell a bit closer to behaving properly. This code is
tons of copy-pasta and needs some love. Because it's not using *any* of
`Chef::Application` (not `Application` or `Application::Base` or even
it's own fork of `Application` like half the other stuff in the repo),
it doesn't have access to _any_ of the many versions of
`load_config_file` (note to self: collapse those into one).
Pulling in Application will be a significant chunk of work, so in the
mean time I did the minimal amount of work to make the `parse_opts` in
shell.rb create the right bits so that Chef::Config and Mixin::DotD can
work... so while this doesn't fix the problem that we're invoking our
own config parsing, it at least uses as much of the common code as I can
without reworking the entirety of chef-shell.
Here's an example of it working:
```
root@ldt-hardwired:~# cinc-shell -s -c /etc/chef/client.rb
loading configuration: /etc/chef/client.rb
true
Session type: solo
```
From there it loads not only `/et/chef/client.rb` but also
`/etc/chef/client.d/ohai.rb`. Neat.
None of this portion of the code is tested in the specs and frankly, I'm
not entirely certainly how to go about writing a test, but I'll poke
around.
fixes #10748
Signed-off-by: Phil Dibowitz <phil@ipom.com>