* #36914: New navigation working

This commit impacts the whole structure app, because we now have
nested Fragments. To keep retro-compatibility, we switched from normal
Fragment to Fragment from the support library.
diff --git a/src/org/sflphone/fragments/DetailsHistoryEntryFragment.java b/src/org/sflphone/fragments/DetailsHistoryEntryFragment.java
index 72b990a..3cd2027 100644
--- a/src/org/sflphone/fragments/DetailsHistoryEntryFragment.java
+++ b/src/org/sflphone/fragments/DetailsHistoryEntryFragment.java
@@ -34,8 +34,6 @@
 import java.io.InvalidObjectException;
 import java.util.ArrayList;
 import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
 import java.util.NavigableMap;
 
 import org.sflphone.R;
@@ -52,7 +50,6 @@
 import android.content.Context;
 import android.os.Bundle;
 import android.os.RemoteException;
-import android.util.Log;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.View.MeasureSpec;
@@ -71,6 +68,7 @@
 
     DetailHistoryAdapter mAdapter;
     HistoryEntry toDisplay;
+    @SuppressWarnings("unused")
     private static final String TAG = DetailsHistoryEntryFragment.class.getSimpleName();
     ContactPictureTask tasker;