Add 9.3 version of iOS to travis.yml.

This should hopefully fix the tests.

Author: Boris-Em

.travis.yml

@@ -1,7 +1,5 @@
 language: objective-c
-osx_image: xcode6.4
-# xcode_project: Sample Project/CheckBox.xcodeproj
-# xcode_scheme: CheckBoxTests
-# xcode_sdk: iphonesimulator
+osx_image: xcode7.3
+
 script:
-  - xcodebuild clean build test -project "Sample Project/CheckBox.xcodeproj" -scheme CheckBox -sdk iphonesimulator ONLY_ACTIVE_ARCH=NO 
+- xcodebuild clean build test -project "Sample Project/CheckBox.xcodeproj" -scheme CheckBox -sdk iphonesimulator9.3 -destination "OS=9.3,name=iPhone 5S" ONLY_ACTIVE_ARCH=NO