Add informative __repr__ for _Feature
Created __repr__ method for geometry types: Point, LineString,
LinearRing, Polygon, Multipoint, MultiLineString, MultiPolygon,
GeometryCollection, and _type = None cases.
The intent of the modification is to have __repr__ return informative
string. For example, __repr__ for LineString instance will return instance
type and the number of coordinate sets associated with the object. The
__repr__ for a Point instance will return a string that allows rebuilding
of the object.
Added test_suite to verify output of geometry __repr__ calls.