Add Test coverage for Hash arguments

Closes [#58].

The `match_response_schema` can be chained off `expect({ ... })` calls,
so add test coverage to ensure that.

[#58]: #58

spec/json_matchers/match_response_schema_spec.rb

@@ -22,6 +22,25 @@
  expect(response_for({})).not_to match_response_schema("foo_schema")
  end
 
+ context "when passed a Hash" do
+ before(:each) do
+ create_schema("foo_schema", {
+ "type" => "object",
+ "required" => [
+ "id",
+ ],
+ "properties" => {
+ "id" => { "type" => "number" },
+ },
+ "additionalProperties" => false,
+ })
+ end
+
+ it "validates when the schema matches" do
+ expect({ "id" => 1 }).to match_response_schema("foo_schema")
+ end
+ end
+
  context "when JSON is a string" do
  before(:each) do
  create_schema("foo_schema", {