adds basic kitchen tests for postgresql cookbook
add initial Test Kitchen integration tests:

* replace initial `bats` setup with `serverspec`
  framework
* add ubuntu-(12|13).04, debian-(6|7) platforms 
* add `default` suite
* add `server` suite with a basic `default_server`
  smoke test
* run with vagrant locally and ec2 on Travis CI
cleanup supporting bundler configuration
simplify `.kitchen.yml` for now:

* only use vagrant locally, skip on CI for now
  until a better long-term solution is available
Merge pull request #67 from phlipper/kitchen_tests

Initial `test-kitchen` suites

closes #65
add rubocop:

* add initial configuration
* add to default test suite
style cleanup and rubocop fixes
Merge pull request #74 from phlipper/rubocop

add rubocop and initial rules
Don't mark wal_writer_delay as a comment
Merge pull request #75 from phlipper/vrischmann/wal_writer_delay

don't mark `wal_writer_delay` as a comment

closes #73
add contribution from @vrischmann to the README
bump version to 0.13.2
consolidate kitchen suites and expand coverage
fix whitespace issues in `pg_user` definition
fix a few issues with database extensions:

* ensure that the `contrib` recipe is included if
  extensions are being installed
* properly handle quoting, and non-quoting, of 
  extension names
skip `postgis` on debian for now:

* PostGIS support on debian is complicated at the
  moment. I'm deferring this until I have more 
  time to spend on it.
Merge pull request #77 from phlipper/regression-test-coverage

add regression test coverage
bump version to 0.13.3
add note indicating that `postgis` is ubuntu-only
busted by rubocop