Loss of precision when writing geometry with more than 6 decimal places to string

[prusswan]

e.g. (103.7940492, 1.4391202) -> 103.794049,1.439120

In geometry.py, _etree_coordinates(self, coordinates) is casting coordinates to %f, reducing the values to 6 decimal places.

[AranVinkItility]

+1 for this, could not find out why my points where not at the intended point on the map.

[MShields1986]

+1

[cleder]

Duplicate of #217

[cleder]

Closing this in favour of #217