Override default merge method for our configuration

For config values of type Array, we don't check for UNSET_VALUE
but only if the array is empty or not

Fix #146
fix rubocop issues
Fix issue #62
Swap call in config_resolver from get_private_networks() to get_all_networks().  Add stub for :get_all_networks in config_resolver_spec so tests will pass
release v0.5.1
Return first adress when multiple are found

Fix #155
Merge pull request #156 from ggiamarchi/fix_multiple_ips

Return first address when multiple are found
Release v0.5.2
Add BatchMode to vagrant ssh options

This way, when ssh prompt us for the password, for instance when the ssh-key
has not yet been setup, we fail the ssh action, and vagrant will retry until
the ssh-key is installed and ssh is really available
Add Glance client
Use Image class instead of Item
Handle Glance endpoint from keystone catalog
Show image details if Glance is available
improve rubocop style and add tests
issue#62 Code review fixing
Merge pull request #158 from ggiamarchi/fix_ssh

Add BatchMode to vagrant ssh options
Merge pull request #154 from simonmazas/issue#62

Fix #62
Merge pull request #159 from ggiamarchi/issue#104

Show image details if Glance is available
Merge branch 'v0.5.x'
Merge pull request #150 from ggiamarchi/issu146

Override default merge method for our configuration