Updated NEWS corresponding to changes in commit #1206 (1.9.3).

git-svn-id: svn+ssh://svn.r-forge.r-project.org/svnroot/datatable@1208 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Test id now printed in dev mode using \r, so we don't have to comment/uncomment

git-svn-id: svn+ssh://svn.r-forge.r-project.org/svnroot/datatable@1209 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Merge branch 'refs/heads/r-forge-git-svn-local'
Fix for #5321 - handling POSIXlt columns during data.table creation.
Fix for #5296. `[.data.table` now retains the same class as the input data.table.