->Bug fixed:
Decoding byte array onPictureTaken to bitmap resulted in total green
pixels. It was due to incorrect camera parameter setting, i.e.
setPictureSize(width, height) with width and height that are not
supported by the camera/phone OS. The bug was fixed by changing the
parameters to values(640*480) with universal support.

->Changes:
1.Removed SurfaceHolder parameter of doTakePic();
Reason: useless, holder has already been passed to MyCamera instance.
2.Removed member byte[] imgData;
Reason: not necessary due to the bug's fix.
3.Removed member ArrayList<byte[]> imgList2;
Reason: not necessary due to the bug's fix.
4.Added Activity PictureActivity to examinate the pictures taken by
camera.

->TO-DO:
1.Finish PictureActivity and add more dynamic capabilities to it.
2.Fix the glitch that the result bitmap was anticlockwise 90 degree.

---Luck