remote query doesn't return variable information for CMIP5

[paolap]

--remote doesn't return variable information for CMIP5 because is based on the dataset_id and the CMIP5 ones don't include the variable.
I thought this was taken care of, probably re-introduced when we moved to the common_esgf.. function.
This doesn't matter so much if you're looking for one variable but it is impossible to work out what's available if you have more than one