[CHEF-4106] Remove obsolete default configuration

Remove default Chef::Config keys that are not used any more.
Most (if not all) of these were used by the Chef server that
is now a separate project.
[CHEF-4176] remove unneeded aliases for chef_server_url
[CHEF-4176] default to https port 443 for chef_server_url
[CHEF-4176] update `knife configure -i` for Chef 11

* Chef 11 defaults to HTTPS on 443
* Chef 11 admin key is in /etc/chef-server/admin.pem
* Chef 11 validator key is in /etc/chef-server/chef-validator.pem

Ref: http://www.opscode.com/blog/2013/03/11/chef-11-server-up-and-running/
[CHEF-4176] reduce duplication in knife configure tests

Tests contain repeated references to the default admin key path,
validator path, and chef_server_url. Replace literals with let bindings
to avoid duplication. This is especially desirable for the negative
tests (e.g. `should_not match`) where drift in the values could render
the tests worthless.
Merge branch 'CHEF-4176'
colored output should be disabled by default on windows
test case for colored output flag for knife
test case for colored output flag for chef client.
rephrase messages related to colored output options change.
Make --[no-]color description more concise
Merge pull request #758 from opscode/adamed-oc-7687-nocolor

OC-7687: Default to --no-color on Windows