* changing the default drive for the config file to be the drive that the executable is launched from.  This should allow for an easier launch of chef from a d: drive installation

Signed-off-by: John Kerry <john@kerryhouse.net>

* adding a check and a fallback to systemdrive for the base path when __FILE__ path doesn't have a drive (appears with linux hosts running windows targeted unit tests)

Signed-off-by: John Kerry <john@kerryhouse.net>

* fixing rubocop errors

Signed-off-by: John Kerry <john@kerryhouse.net>

* adding a __FILE__ path override for cache_path tests

Signed-off-by: John Kerry <john@kerryhouse.net>

Third-party data collector implementations are supported and may not
require a token for authentication. Therefore we must allow the case
where the token is nil in Chef Solo mode. To reduce the chance that the
data collector is accidentally enabled, only set the data collector URL
to a default value in Chef Client mode.

Signed-off-by: Daniel DeLeo <dan@chef.io>

Additionally, add info and debug logging for the auto-detection of
whether to enable the data collector.

Signed-off-by: Daniel DeLeo <dan@chef.io>

Signed-off-by: Daniel DeLeo <dan@chef.io>

The `--config-option` CLI option allows setting any `Chef::Config`
setting on the command line, which allows applications to be used
without a configuration file even if a desired config option does not
have a corresponding CLI option. This CLI option was present in the help
output for knife but was not actually implemented. Moving the behavior
into chef-config allows us to use it for both `chef-client` and `knife`.

Signed-off-by: Daniel DeLeo <dan@chef.io>