[datatable-help] data.table 1.4

[Matthew Dowle]

1.4 is merged to mainline now.

Main change is further speed improvements for grouping e.g. 10 times
faster than tapply and aggregate.

Although the r-forge package tab displays its at 1.4, it seems it didn't
fully update behind the scenes last night, have raised ticket.  Similar
things have happened before, and if its the same, it should hopefully
update tonight. In the meantime, install.packages() will probably still
grab v1.3.  It might even install v1.3 but report that its installed
v1.4.  Will check again tomorrow.

Matthew