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[hrbrmstr]

As of Drill 1.15.0 we now know the data types of things returned so we can use this to have proper 64-bit integers as well as proper types all 'round.

[hrbrmstr]

this will also fix #10

[hrbrmstr]

In the interim, a new warning will be displayed when BIGINTs are encountered (but only once per R session just as a reminder).