Changes in new version

Version agricolae 1-1.8 (February 21, 2014)
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* zigzag(outdesign)
The new function applied to designs: rcbd, lsd, graeco, split, strip, ab, alpha, bib, cyclic,
lattice, dau. The outdesign is the output book the function design.###().
The function zigzag change the order number plots in serpentine form.
# Randomized complete design.
trt<-LETTERS[1:5]
outdesign<-design.rcbd(trt,r=4, serie=2)
book<-outdesign$book
> t(matrix(book[,1],5))
     [,1] [,2] [,3] [,4] [,5]
[1,]  101  102  103  104  105
[2,]  201  202  203  204  205
[3,]  301  302  303  304  305
[4,]  401  402  403  404  405
fieldbook <- zigzag(outdesign)
> t(matrix(fieldbook[,1],5))
     [,1] [,2] [,3] [,4] [,5]
[1,]  101  102  103  104  105
[2,]  205  204  203  202  201
[3,]  301  302  303  304  305
[4,]  405  404  403  402  401

* Now, all design functions have two output objects: parameters and book, the parameters contain initial values that will allow reproduce the design and book contain field book.
* The alpha and lattice designs have additionally two objects: statistics and 
field sketches. 
* BIB have the statistics with parameters and field book.
* Cyclic have the stetches with parameters and field book.


