[R-pkgs] new version of lattice

[Deepayan Sarkar]

[This is more a warning than an announcement]

A new version of lattice should be soon on CRAN. From this version onwards, 
all high-level lattice functions are (S3) generic. All of them have formula 
methods, some have other methods as well, formalizing the various non-formula 
uses which used to be handled by clumsy hacks in the past. There's also a new 
table method for barchart.

Ideally, this change should be completely transparent to the user and no 
existing code should break (except undocumented and inappropriate examples 
like 

dotplot( x  | a )

which used to work like dotplot(~x | a) before). However, Murphy's law usually 
prevails, so...

Deepayan