1.6

* S3 methods predict.cgam is registered in 'NAMESPACE' 
* new routine ShapeSelect is included, which does variable and shape selection
* new routines in.or.out and select are included
* S3 methods plot.shapeselect is registered in 'NAMESPACE' 
* debug in wps, ps = max(1e-6, 1 * sc)
* change all diag(w) in matrix production in cgam.fit in order to avoid memory allocation problems
* change categ = factor(z) in plotpersp.cgam
* change tree.fun to make 0 as default and allow characters
* debug null dev in poisson 
* add sc_x and sc_y in cgam to scale x or y
* add best.fit(fit) for the ShapeSelect routine
* arrange x's into the original order if some shape is 17
