Force permissions to private key file to 600

Related to #101
Fix unit test
Pre-release 0.3.4.pre
replace debugger by byebug for debugging
Fix network endpoint resolution

fix #112
Merge pull request #116 from ggiamarchi/issue#112

Fix network endpoint resolution
Release 0.4.1
Merge pull request #102 from ggiamarchi/fix_permissions

Force permissions to private key file to 600
Update README
Update README.md
Make box optional

Fix #105
Merge pull request #124 from ggiamarchi/update_readme

Update README
Adding a base64 encoding to the user data in the server creation
Merge pull request #126 from mael-morel/issue-122

Adding a base64 encoding to the user data in the server creation
Merge pull request #125 from ggiamarchi/issue#105

Make box optional
Merge pull request #113 from smo921/public_networks

Public networks
Enhance command args handling for vagrant 1.4 compatibility
Remove useless EOL in command output
Merge pull request #127 from ggiamarchi/v0.4.x

v0.4.1 Backport
Update Vagrantfile