1.0.5	fixed some minor bugs
1.0.4	fixed some minor bugs

1.0.3	now mixed.mtc() can handle also categorical common variables

		fixed a bug in comb.samples() when handling factor levels

		new error messages in RANDwNND.hotdeck() when computing ditances 
		between units with missing values

1.0.2   new function mahalanobis.dist() to compute the mahalanobis distance

		fixed a bug in mixed.mtc() when computing the range of admissible values
		for rho_yz
		
		fixed a bug in NND.hotdeck()  and RANDwNND.hotdeck() when
		managing the row.names
		
1.0.1	new functions harmonize.x() and comb.samples() to perform statistical
		matching when dealing with complex sample survey data via 
		weight calibration.

		new function Frechet.bounds.cat() to explore uncertainty when dealing with 
		categorical variables. The function Fbwidths.by.x()	permits to
		identify the subset of the common variables that performs better in reducing 
		uncertainty
		
		New function rankNND.hotdeck() to perform rank hot deck distance
		
		Update of RANDwNND.hotdeck() to use donor weight in selecting a donor
		
		new function maximum.dist() that computes ddistances according to the
		L^Inf norm. A rank trasnformation of the variables can be used.
		
0.8    fixed some bugs in NND.hotdeck() and RANDwNND.hotdeck()

