Kuba/5626 integer table column formats (#5646)
Kuba/5626 integer table column formats (#5646)

* #5626 add support for int64; datatime parser for integers (unix-seconds)

* #5626 remove commented out code

jpallas/beakerx,jpallas/beakerx,twosigma/beaker-notebook,jpallas/beakerx,twosigma/beakerx,twosigma/beaker-notebook,twosigma/beakerx,jpallas/beakerx,twosigma/beakerx,twosigma/beakerx,twosigma/beakerx,twosigma/beakerx,twosigma/beaker-notebook,twosigma/beaker-notebook,jpallas/beakerx,jpallas/beakerx,twosigma/beaker-notebook