ViewModel refactoring: Permissions part

Add MyDbHelper and MyRepository, use database to store dhizuku clients,
fix #168

app/src/main/java/com/bintianqi/owndroid/MyApplication.kt

@@ -5,12 +5,14 @@ import android.os.Build.VERSION
 import org.lsposed.hiddenapibypass.HiddenApiBypass
 
 class MyApplication : Application() {
+    lateinit var myRepo: MyRepository
     override fun onCreate() {
         super.onCreate()
         if (VERSION.SDK_INT >= 28) HiddenApiBypass.setHiddenApiExemptions("")
         SP = SharedPrefs(applicationContext)
+        val dbHelper = MyDbHelper(this)
+        myRepo = MyRepository(dbHelper)
         Privilege.initialize(applicationContext)
-        Privilege.updateStatus()
     }
 }