[read_wkt] Don't append duplicated, closing Points in open Rings/Polygons.

Note that Points are still appended if there is not enough Points in the input, i.e. the number is < 3 for open Rings.
[test] Update tests to be in line with the change in behavior of read_wkt() for open Rings.
[test] Remove temporary/unneeded code in point_iterator test.
[from_wkt] Move the appending logic outside container_appender and dispatch by closure.
[from_wkt] Add default template parameters to parsing_assigner.
Merge branch 'develop' into fix/read_wkt
Merge branch 'develop' into fix/read_wkt
[read_wkt] Remove unnecessary remove_reference usage.
Merge branch 'develop' into fix/read_wkt
Merge pull request #160 from awulkiew/fix/read_wkt

Fix/read wkt