SQL util functions

[andresmgot]

Ref: grafana/grafana-aws-sdk#28

This PR includes some more functions shared between SQL datasources (used in Suggestions and the Datasource class).

[sunker]

The functions in the utils file doesn't really seems aws plugin specific, but more SQL plugin specific. The filterQuery function would not be usable in the X-ray plugin for example. I know we've talked about introducing a new, SQL package at some point. But for now, can we rename that function or the util file in some way so that it becomes obvious that this is only applicable for SQL plugins?

[andresmgot]

But for now, can we rename that function or the util file in some way so that it becomes obvious that this is only applicable for SQL plugins?

I am okay changing the name of the function but this is nicely covered by typescript. The function filterQuery is expecting a SQLQuery as an argument (this is a query with the value rawSQL) so this could not be used by X-ray. In any case, I am fine making the function names explicit.

[sunker]

Nice!