drop support to Ruby 1.9.3 from build matrix

Author: KaraAJC

.travis.yml

@@ -3,7 +3,6 @@ language: ruby
 sudo: false
 
 rvm:
-  - 1.9.3
   - 2.0.0
   - 2.1
   - 2.2.3
@@ -26,8 +25,6 @@ env:
 
 matrix:
   exclude:
-  - rvm: 1.9.3
-    env: RAILS_VERSION=master
   - rvm: 2.0.0
     env: RAILS_VERSION=master
   - rvm: 2.1

CHANGELOG.md

@@ -25,6 +25,7 @@ Features:
     CollectionSerializer for clarity, add ActiveModelSerializers.config.collection_serializer (@bf4)
 
 Fixes:
+- [#1360](https://github.com/rails-api/active_model_serializers/pull/1360) Update Travis CI build matrix with ruby 2.2.3 supporting rails5 (@karaAJC)
 - [#1239](https://github.com/rails-api/active_model_serializers/pull/1239) Fix duplicates in JSON API compound documents (@beauby)
 - [#1214](https://github.com/rails-api/active_model_serializers/pull/1214) retrieve the key from the reflection options when building associations (@NullVoxPopuli, @hut8)
 - [#1358](https://github.com/rails-api/active_model_serializers/pull/1358) Handle serializer file paths with spaces (@rwstauner, @bf4)