Schema causes RegexpError: empty range in char class

[kjwierenga]

I'm using the Ruby JSON Schema Validator (https://github.com/ruby-json-schema/json-schema) and an accompanying matcher to match API responses to JSON schema definitions.

When I match against the JSONAPI schema found at http://jsonapi.org/schema I get the following error:

 Failure/Error: response.body.should match_json_schema('json-api')
 RegexpError:
   empty range in char class: /^(?!relationships$|links$)\w[\w-_]*$/

The [\w-_] char class seems to be a problem.
See also: http://stackoverflow.com/questions/13161903/regular-expression-empty-range-in-char-class-error

The solution is to move the dash to the front of the char class like so: [-\w_]. I'll supply a PR shortly.

[bf4]

Closed by #830 :)