Pass lat-lon points to BallTree instead of lon-lat

[stelliom]

Description

The haversine distance metric for sklearn's BallTree requires the points to be passed in lat-lon format (see docs). We were passing those in lon-lat format, causing large errors (smoothing/"dripping" artifacts) around 90E and 90W longitude lines.

Passing the points in lat-lon format seems to solve the issue.

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[stelliom]

launch jenkins

[stelliom]

launch jenkins