Replace ChefSpec::Runner.define_runner_method w/ ChefSpec.define_matcher

As per ChefSpec deprecations warnings
Update gems to latest & greatest

Big ones:

* berkshelf
* chefspec
* chef-zero
Move kitchen-vagrant to its own group

No need to install it when testing via Travis CI
De-dupe Rake tasks
Refactor Travis config to work more smoothly
Ignore Coveralls reports
Update spec_helper to work w/ Serverspec 2
Bump to v1.4.1