android Set subtitle to zimfile title.

null apparently just clear subtitle which is fine

src/org/kiwix/kiwixmobile/KiwixMobileActivity.java

@@ -378,6 +378,9 @@ public class KiwixMobileActivity extends Activity {
 	private boolean openZimFile(File file, boolean clearHistory) {
 		if (file.exists()) {
 			if (ZimContentProvider.setZimFile(file.getAbsolutePath())!=null) {
+
+
+        		getActionBar().setSubtitle(ZimContentProvider.getZimFileTitle());
 				//Apparently with webView.clearHistory() only 
 				//    history before currently (fully) loaded page is cleared
 				// -> request clear, actual clear done after load.

src/org/kiwix/kiwixmobile/ZimContentProvider.java

@@ -58,6 +58,19 @@ public class ZimContentProvider extends ContentProvider {
 	public static String getZimFile() {
 		return zimFileName;
 	}
+	public static String getZimFileTitle() {
+		if (jniKiwix==null)
+			return null;
+		else {
+			JNIKiwixString title = new JNIKiwixString();
+			if (jniKiwix.getTitle(title)) {
+				return title.value;
+			}
+			else return null;
+		}
+	}
+	
+    public native boolean getTitle(JNIKiwixString title);
     
 	public static String getMainPage() {
 		if (jniKiwix==null)