Use path_join to create local-mode-cache
Always give config_dir a value
CHANGELOG.md for 1854
Merge pull request #1854 from opscode/lcg/config_dir

Use path_join to create local-mode-cache
CHEF-4101: DeepMerge - support overwriting hash values with nil
add CHANGELOG.md for PR#719
Merge pull request #1851 from opscode/lcg/chef-4101

CHEF-4101: DeepMerge - support overwriting hash values with nil