Update CI

.travis.yml

@@ -4,7 +4,7 @@ os:
 language: generic
 sudo: required
 dist: trusty
-osx_image: xcode9.2
+osx_image: xcode10.2
 script:
   - eval "$(curl -sL https://raw.githubusercontent.com/onevcat/Swift-CI/master/ci)"
   - eval "$(curl -sL https://raw.githubusercontent.com/onevcat/Swift-CI/master/codecov)"

README.md

@@ -4,7 +4,7 @@
 
 <p align="center">
 <a href="https://travis-ci.org/onevcat/FengNiao"><img src="https://img.shields.io/travis/onevcat/FengNiao/master.svg"></a>
-<a href="https://swift.org/package-manager/"><img src="https://img.shields.io/badge/swift-4.0-brightgreen.svg"/></a>
+<a href="https://swift.org/package-manager/"><img src="https://img.shields.io/badge/swift-4.0+-brightgreen.svg"/></a>
 <a href="https://swift.org/package-manager/"><img src="https://img.shields.io/badge/SPM-ready-orange.svg"></a>
 <a href="https://raw.githubusercontent.com/onevcat/Kingfisher/master/LICENSE"><img src="https://img.shields.io/cocoapods/l/Kingfisher.svg?style=flat"></a>
 <a href="https://swift.org/package-manager/"><img src="https://img.shields.io/badge/platform-macos%20|%20Linux-blue.svg"/></a>