src/*.{h,c} long -> int

man/*.Rd  convert *.d by Sd2Rd

Don't implement code using naresid, which R does not have.
F -> FALSE, T -> TRUE

R/labels.rpart.s	replace call to prlabel by S code.
R/model.frame.rpart.s 	deparse calls
R/na.rpart.s		as x has no attributes in R, redesign
R/plot.rpart.s 		change frame=0 to .GlobalEnv
R/post.rpart.s		change `title' trickery
R/print.rpart.s		remove nsmall in call to format
			attr(x, 'ylevels') not 'ylevel'
R/rpart.branch.s	get with inherits not frame=0
R/rpart.matrix.s	adjust for different terms structure
R/rpart.s		single -> double
			sys.parent() -> sys.frame(sys.parent())
R/rpartco.s		remove frame=0 several times
R/snip.rpart.mouse.s	drop frame=0
R/summary.rpart.s	remove justify="left" in format
			remove comma in paste(... ,,collapse ...)
			attr(x, 'ylevels') not 'ylevel'
R/text.rpart.s		text.default prints "NA", so remove these
			remove density=0 in calls to polygon
R/xpred.rpart.s		single -> double
			sys.parent() -> sys.frame(sys.parent())
R/zzz.R			a few missing functions.

