v0.5.5

This release makes a few changes to plpygis behaviour:

• WKTs again default to 6 decimal places of precision but this is now configurable using plpygis.wkt.PRECISION.
• plpygis will ensure that there are the required number of coordinates when reading a LineString or Polygon from a WKT and will raise a WktError when there are not enough (note that plpygis does not guarantee valid geometries beyond these simple checks).
• geojson could return m values instead of z values for LineStrings and Polygons but this is no longer possible.
• There were cases where scientific notation could appear in(E)WKT output but this is also no longer possible.

Full Changelog: v0.5.4...v0.5.5