move all preference related stuff in prefs subfolder

mobile/src/com/cradle/iitc_mobile/prefs/ForceUpdatePreference.java

@@ -0,0 +1,49 @@
+package com.cradle.iitc_mobile.prefs;
+
+import android.app.AlertDialog;
+import android.content.Context;
+import android.content.DialogInterface;
+import android.preference.Preference;
+import android.preference.PreferenceManager;
+import android.util.AttributeSet;
+
+import com.cradle.iitc_mobile.R;
+
+/**
+ * The OptionDialogPreference will display a dialog, and will persist the
+ * <code>true</code> when pressing the positive button and <code>false</code>
+ * otherwise. It will persist to the android:key specified in xml-preference.
+ */
+public class ForceUpdatePreference extends Preference {
+
+    public ForceUpdatePreference(Context context, AttributeSet attrs) {
+        super(context, attrs);
+    }
+
+    @Override
+    protected void onClick() {
+        super.onClick();
+        new AlertDialog.Builder(getContext())
+                .setTitle(R.string.pref_force_plugin_update)
+                .setMessage(R.string.pref_force_plugin_update_sum)
+                .setCancelable(true)
+                .setPositiveButton("OK", new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialog, int which) {
+                        PreferenceManager.getDefaultSharedPreferences(getContext())
+                                .edit()
+                                .putLong("pref_last_plugin_update", 0)
+                                .commit();
+                        dialog.cancel();
+                    }
+                })
+                .setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialog, int which) {
+                        dialog.cancel();
+                    }
+                })
+                .create()
+                .show();
+    }
+}