validate not specified Vagrantfile without internet connection
add `cache_packages` config option, if enabled and cachier present pass `-d` to install.sh as the cache dir
fix wrong config value (returned `Vagrant::Config::V2::DummyConfig` but not nil!)
expose an `install_script` config option for specifying a custom install.sh. The env var still works but has lower precedence
less but more realistic spec examples
naming things is hard...: rename `install_script` to `install_url`
describe newly added config options in README
fix rubocop warnings reported on travis but not locally?!?
temporary pin to rubocop 0.18.1 until bbatsov/rubocop#892 is released
Merge pull request #67 from skv-headless/master

validate not specified Vagrantfile without internet connection
Merge pull request #73 from tknerr/cache-omnibus-download-via-config-rebased

Cache omnibus download, expose config options (rebased)
Bump `vagrant` and `vagrant-windows` versions
fix rake tasks not calling the proper acceptance tests
Merge branch 'pr/72'
Speed up bundle install in Travis