Use app.* instead of ShadowsocksApplication.*

Because typing ShadowsocksApplication is quite troublesome.

src/main/scala/com/github/shadowsocks/ShadowsocksApplication.scala

@@ -45,26 +45,32 @@ import java.util.concurrent.TimeUnit
 import android.app.Application
 import android.content.pm.PackageManager
 import android.preference.PreferenceManager
-import com.j256.ormlite.logger.LocalLog
 import com.github.shadowsocks.database.{DBHelper, ProfileManager}
 import com.github.shadowsocks.utils.{Key, Utils}
 import com.google.android.gms.analytics.{GoogleAnalytics, HitBuilders}
 import com.google.android.gms.common.api.ResultCallback
 import com.google.android.gms.tagmanager.{ContainerHolder, TagManager}
+import com.j256.ormlite.logger.LocalLog
 
 object ShadowsocksApplication {
-  var instance: ShadowsocksApplication = _
-  lazy val dbHelper = new DBHelper(instance)
+  var app: ShadowsocksApplication = _
+}
+
+class ShadowsocksApplication extends Application {
+  import ShadowsocksApplication._
+
+  lazy val dbHelper = new DBHelper(this)
   final val SIG_FUNC = "getSignature"
   var containerHolder: ContainerHolder = _
-  lazy val tracker = GoogleAnalytics.getInstance(instance).newTracker(R.xml.tracker)
-  lazy val settings = PreferenceManager.getDefaultSharedPreferences(instance)
+  lazy val tracker = GoogleAnalytics.getInstance(this).newTracker(R.xml.tracker)
+  lazy val settings = PreferenceManager.getDefaultSharedPreferences(this)
+  lazy val editor = settings.edit
   lazy val profileManager = new ProfileManager(settings, dbHelper)
 
   def isVpnEnabled = !settings.getBoolean(Key.isNAT, false)
 
   def getVersionName = try {
-    instance.getPackageManager.getPackageInfo(instance.getPackageName, 0).versionName
+    getPackageManager.getPackageInfo(getPackageName, 0).versionName
   } catch {
     case _: PackageManager.NameNotFoundException => "Package name not found"
     case _: Throwable => null
@@ -84,14 +90,10 @@ object ShadowsocksApplication {
     profileId(id)
     profileManager.load(id)
   }
-}
-
-class ShadowsocksApplication extends Application {
-  import ShadowsocksApplication._
 
   override def onCreate() {
-    java.lang.System.setProperty(LocalLog.LOCAL_LOG_LEVEL_PROPERTY, "ERROR");
-    ShadowsocksApplication.instance = this
+    java.lang.System.setProperty(LocalLog.LOCAL_LOG_LEVEL_PROPERTY, "ERROR")
+    app = this
     val tm = TagManager.getInstance(this)
     val pending = tm.loadContainerPreferNonDefault("GTM-NT8WS8", R.raw.gtm_default_container)
     val callback = new ResultCallback[ContainerHolder] {