Update platform target to 8.1 (API level 27)

build.sbt

@@ -4,7 +4,7 @@ lazy val commonSettings = Seq(
 
   organization := "com.github.shadowsocks",
 
-  platformTarget := "android-26",
+  platformTarget := "android-27",
 
   compileOrder := CompileOrder.JavaThenScala,
   javacOptions ++= "-source" :: "1.7" :: "-target" :: "1.7" :: Nil,
@@ -23,7 +23,7 @@ lazy val commonSettings = Seq(
   resolvers += "google" at "https://maven.google.com"
 )
 
-val supportLibsVersion = "26.1.0"
+val supportLibsVersion = "27.0.0"
 lazy val root = Project(id = "shadowsocks-android", base = file("."))
   .settings(commonSettings)
   .aggregate(plugin, mobile)

mobile/src/main/AndroidManifest.xml

@@ -17,7 +17,7 @@
 
     <uses-sdk
             android:minSdkVersion="19"
-            android:targetSdkVersion="26"/>
+            android:targetSdkVersion="27"/>
 
     <meta-data android:name="android.webkit.WebView.EnableSafeBrowsing"
                android:value="true" />

plugin/src/main/AndroidManifest.xml

@@ -2,7 +2,7 @@
           package="com.github.shadowsocks.plugin">
     <uses-sdk
             android:minSdkVersion="19"
-            android:targetSdkVersion="26"/>
+            android:targetSdkVersion="27"/>
     <application
             android:theme="@style/Theme.Shadowsocks">
         <meta-data android:name="com.github.shadowsocks.plugin.version"