Some more little fixes

- AndroidManifest.xml, add android:exported attribute to <activity> as recommended by Android Studio
- Add back missing rar extension to FileUtils.COMPRESSED_FILE_EXTENSIONS which prevented RAR files be opened by Amaze for viewing

Author: TranceLove

app/src/main/AndroidManifest.xml

@@ -150,7 +150,8 @@
             android:launchMode="singleInstance"
             android:name=".ui.activities.MainActivity"
             android:theme="@style/appCompatBlack"
-            android:configChanges="uiMode" >
+            android:configChanges="uiMode"
+            android:exported="true">
 
             <intent-filter android:label="@string/appbar_name">
                 <action android:name="android.intent.action.MAIN" />
@@ -217,7 +218,8 @@
             android:configChanges="orientation|screenSize|uiMode"
             android:label="@string/setting"
             android:name=".ui.activities.PreferencesActivity"
-            android:theme="@style/appCompatBlack">
+            android:theme="@style/appCompatBlack"
+            android:exported="false">
             <intent-filter>
                 <action android:name="android.intent.action.APPLICATION_PREFERENCES" />
                 <category android:name="android.intent.category.DEFAULT" />
@@ -228,7 +230,8 @@
             android:label="@string/textreader"
             android:name=".ui.activities.texteditor.TextEditorActivity"
             android:configChanges="uiMode"
-            android:theme="@style/appCompatBlack">
+            android:theme="@style/appCompatBlack"
+            android:exported="true">
             <intent-filter
                 tools:ignore="AppLinkUrlError"
                 android:label="Amaze Text Editor">
@@ -242,6 +245,7 @@
 
         </activity>
         <activity
+            android:exported="true"
             android:label="@string/databasereader"
             android:name=".ui.activities.DatabaseViewerActivity"
             android:theme="@style/appCompatBlack"
@@ -303,7 +307,8 @@
         <service android:name=".asynchronous.services.ftp.FtpTileService"
             android:icon="@drawable/ic_ftp_dark"
             android:label="@string/ftp"
-            android:permission="android.permission.BIND_QUICK_SETTINGS_TILE">
+            android:permission="android.permission.BIND_QUICK_SETTINGS_TILE"
+            android:exported="false">
             <intent-filter>
                 <action
                     android:name="android.service.quicksettings.action.QS_TILE" />

app/src/main/java/com/amaze/filemanager/filesystem/files/FileUtils.java

@@ -96,7 +96,7 @@ public class FileUtils {
   private static final String TAG = FileUtils.class.getSimpleName();
 
   private static final String[] COMPRESSED_FILE_EXTENSIONS =
-      new String[] {"zip", "cab", "bz2", "ace", "bz", "gz", "7z", "jar", "apk", "xz", "lzma", "Z"};
+      new String[] {"zip", "cab", "bz2", "ace", "bz", "gz", "7z", "jar", "apk", "xz", "lzma", "Z", "rar"};
 
   public static final String FILE_PROVIDER_PREFIX = "storage_root";
   public static final String NOMEDIA_FILE = ".nomedia";