[multi][core] Move functionalities of multi/core into core
[multi][views] Move range_type<> from multi/ directory.

Also tweak the parameters of the dispatched implementation - reverse the order and add default Tag.
[multi][strategies] Move centroid_average from multi/ directory
[multi][geometries] Move models, concepts and register macros from multi/ directory
[multi][io] Move wkt and dsv implementation for Multi Geometries from multi/ directory
[multi] Include headers of moved parts from geometry/ directory.
[geometry] Replace headers of parts moved from multi/ directory.
[multi][algorithm/detail] Move most of the code of details from multi/ directory.

This commit doesn't move for_each_range.
Details used only by multi/algorithms aren't moved as well.
[multi] Move algorithms details used only by multi/algorithm from multi/ directory.
[algorithms/detail] Refactor for_each_range and move it from multi/directory.
[algorithms/detail] Fix for_each_range backward compatibility.

In the specialization for Box remove_const before creating box_view<> and passing the object of this type into the Actor::apply().
[geometry] Replace includes of headers from algorithms/detail moved from multi/ directory.
[extensions] Replace includes of headers moved from multi/ directory.
[doc] Update docs WRT the latest relocation of the code from multi/ directory
[example] Update examples WRT the latest relocation of the code from multi/ directory
[docutils] Update WRT the latest relocation of the code from multi/ directory.

Also add Jamfile for support_status.
[extensions/example] Update #includes WRT the latest relocation of the code from multi/ directory
[multi] Remove multi-geometries concepts from multi/multi.hpp since they are included in geometries/concepts/check.hpp
Merge pull request #55 from awulkiew/refactor_multi

Moving geometry/multi/ into geometry/