From 4.5 to 4.6:	Moved all references from nlevels() to nlevelsWT()

4.7:	Introduced the JRSSB paper reference into some of the help files.
	Added registration of S3Methods and also imports directives to NAMESPACE
	Also added restriction to only analyse vectors of length >= 8,
	as wd doesn't deal well with small length vectors by default 
	Added print.wb and summary.wb methods
	Added init.c to src directory and registered native routines.

4.7.1   Move some C source code (comwr, comcbr and commul) from wavethresh
	to here. This is because R packages no longer permit borrowing
	code from other packages.
