[CHEF-5158] knife[:attribute] in knife.rb should not override --attribute in the command line
CHEF-5158: Make the former override_attribute's purpose a bit more clear
CHEF-5158: Add some debugging information for knife ssh attribute
CHEF-5158: Contribution notes
Merge pull request #1530 from opscode/btm/CHEF-5158

CHEF-5158: Prefer CLI argument over configuration file setting for ssh_attribute