forgot 2 other references for changing default format to json

Author: Jerry Cheung

lib/grape/endpoint.rb

@@ -276,7 +276,7 @@ def build_middleware
 
       b.use Grape::Middleware::Formatter,
         :format => settings[:format],
-        :default_format => settings[:default_format] || :txt,
+        :default_format => settings[:default_format] || :json,
         :content_types => settings[:content_types]
 
       aggregate_setting(:middleware).each do |m|

spec/grape/api_spec.rb

@@ -320,12 +320,12 @@ def app; subject end
 
     it 'should set content type for txt format' do
       get '/foo'
-      last_response.headers['Content-Type'].should eql 'text/plain'
+      last_response.headers['Content-Type'].should eql 'application/json'
     end
 
-    it 'should set content type for json' do
-      get '/foo.json'
-      last_response.headers['Content-Type'].should eql 'application/json'
+    it 'should set content type for txt' do
+      get '/foo.txt'
+      last_response.headers['Content-Type'].should eql 'text/plain'
     end
 
     it 'should set content type for error' do