Throw parser error for invalid aggregate without where time

[corylanou]

If you issue a query like so:

select count(value) from cpu group by time(1d)

It would effectively return an empty result set, but not error out.

Should error out with something like:

error parsing query: COUNT with GROUP BY time requires WHERE time clause

The correct syntax is to provide a WHERE with a time condition like so:

select count(value) from cpu where time > now() - 30d group by time(1d)