Changes:
- Use libtiff>3.8.
- bit order is different from byte order. So don't messup endianness
with LSBfirst in bitmaps.
- Added support for Lab up to 3x16bits and RGB/RGBA up to 4x32bits.
Qt3 and Qt4 QImage class. Adding the generated plugin in the Qt's
tree enable any Qt application to manipulate TIFF images. TiffIO come
with a self-test suite, and have been compiled and used successfully
on a variety of windows and unixes platforms.