[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
[index] Remove unneeded file.
[index] Remove unneeded create_node<> specializations.
[index] Replace struct with class keyword in specialization of allocators<> for variant-based static-size node.
[buffer] Performance boost: added trivial check which in some cases
can speed up the buffer process 50%
Merge branch 'develop' of github.com:boostorg/geometry into develop
[overlay] change default_order using index instead of address
[buffer][overlay][fix] Fix order in tangencies iu/iu case
[warn] avoid unused variable warning in distance concept
Merge pull request #181 from awulkiew/feature/geographic

Feature/geographic
Merge pull request #160 from awulkiew/fix/read_wkt

Fix/read wkt