FileExplorer

Update at 2010/05/04
1. fix a ANR issue.
2. add .apk file support.

Update at 2010/04/27
1. Access sdcard files freely.
2. Display video thumbnail or albumart.
3. Send file to bluetooth.
4. Open text file in browser.
5. playback audio/video freely.
6. support .sdp file playback.
7. support browser local html file in sdcard.