Merge pull request #22 from keithito/update-ci

Update Travis to use xcode 10.1, check carthage build

.travis.yml

@@ -3,9 +3,10 @@
 # * https://github.com/supermarin/xcpretty#usage
 
 language: objective-c
-osx_image: xcode9
+osx_image: xcode10.1
 before_install:
 - gem install cocoapods xcpretty --no-rdoc --no-ri --no-document --quiet
 script:
-- set -o pipefail && xcodebuild test -workspace SimpleAnimation.xcworkspace -scheme SimpleAnimation -sdk iphonesimulator -destination 'platform=iOS Simulator,name=iPhone 6,OS=11.0' ONLY_ACTIVE_ARCH=NO | xcpretty
+- set -o pipefail && xcodebuild test -workspace SimpleAnimation.xcworkspace -scheme SimpleAnimation -sdk iphonesimulator -destination 'platform=iOS Simulator,name=iPhone 6,OS=12.1' ONLY_ACTIVE_ARCH=NO | xcpretty
 - pod lib lint --quick
+- carthage build --no-skip-current