Fix typo.
Use TestNG asserts
JCLOUDS-265: Add listEnvironmentNodes API in ChefService
Cleanup tests

* Use TestNG assertions
* Formatted code in compute tests
* Removed unnecessary local variables in tests to avoid using them by
  mistake between independent tests.
JCLOUDS-253: Properly parse Chef Server version
Cleaned up ChefApi and ChefService interfaces

Cleaned up and renamed some methods to have a more consistent naming,
and improved the javadocs.
Improved javadoc and parameter naming
JCLOUDS-272: Migrate unit tests from ChefApiTest to ChefApiExpectTest.
Renamed test methods to match the new api naming convention
Renamed test methods and file names to match the new api naming convention
Use meaningful parameter name in ParseKeySetFromJson
Use meaningful parameter name in ParseSearchResultFromJson and ParseSearchDatabagFromJson.

Also use static import for Sets and Iterables.
JCLOUDS-285: Add name field in CookbookDefinition domain
Removed unused imports
Make listCookbooksInEnvironment return an empty set on 404

Added tests to validate above.
Also factored out some duplicate code in test.
JCLOUDS-286: Use by default the Omnibus installer
Rename test method names to reflect what is being tested.
JCLOUDS-272: Migrate search role tests from ChefApiTest to ChefApiExpectTest.