Reshape the dataset from long format to wide format.
Arguments
- dt
 Dataset to be reshaped
- respec
 Reshape specification with
idandvaluevariables. This is the output fromget_reshape_wide_spec()
See also
Other reshape functions:
do_reshape(),
do_reshape_long(),
do_reshape_rename_col(),
get_reshape_id_val(),
get_reshape_wide_spec()
