Add URLs to API responses

Resolves inability of API consumers to provide links to OSEM.

spec/serializers/event_serializer_spec.rb

@@ -9,6 +9,7 @@ describe EventSerializer, type: :serializer do
     it 'sets guid, title, length, abstract and type' do
       expected_json = {
         guid:           event.guid,
+        url:            "http://localhost:3000/conferences/#{event.conference.short_title}/program/proposals/#{event.id}",
         title:          'Some Talk',
         length:         30,
         scheduled_date: '',
@@ -39,6 +40,7 @@ describe EventSerializer, type: :serializer do
     it 'sets guid, title, length, abstract, type, date, language, speakers, room and track' do
       expected_json = {
         guid:           event.guid,
+        url:            "http://localhost:3000/conferences/#{event.conference.short_title}/program/proposals/#{event.id}",
         title:          'Some Talk',
         length:         30,
         scheduled_date: ' 2014-03-04T09:00:00+0000 ',

spec/serializers/speaker_serializer_spec.rb

@@ -8,6 +8,7 @@ describe SpeakerSerializer, type: :serializer do
   context 'speaker does not have biography' do
     it 'sets name and affiliation' do
       expected_json = {
+        url:         "http://localhost:3000/users/#{speaker.id}",
         name:        'John Doe',
         affiliation: 'JohnDoesInc',
         biography:   nil
@@ -22,6 +23,7 @@ describe SpeakerSerializer, type: :serializer do
 
     it 'sets name, affiliation and biography' do
       expected_json = {
+        url:         "http://localhost:3000/users/#{speaker.id}",
         name:        'John Doe',
         affiliation: 'JohnDoesInc',
         biography:   'Doest of all Jon Does'

spec/support/schemas/conference.json

@@ -3,6 +3,7 @@
     "type" : "object",
     "required" : [
       "short_title",
+      "url",
       "title",
       "description",
       "start_date",
@@ -19,6 +20,9 @@
       "short_title": {
         "type": "string"
       },
+      "url": {
+        "type": "string"
+      },
       "title": {
         "type": "string"
       },