Bump version to v1.1.1 for development
Use apt_preference to create the repo pinning rule

apt cookbook supports package_name attribute since v1.6.0,
thus allowing passing `*` to it.
Put Vagrant and Berkshelf gems to :development group

Make it easier to exclude them on a CI server.
Add foodcritic test
Add Travis configuration and badge
Add knife cookbook test
Test also older Chef versions
Merge branch 'tests'

Add foodcritic and knife tests. A good start for #2.
Remove obsolete apt_preferences template

Not used after commit 00b71a12.