Fix behavior of allocator_adaptor on NULL pointer
Renamed and moved container category
Refurbished options and options retrieval

Options of container are now responsible of computing their related
types and values. Moreover, the options fetching code is simplified
and put back the semantic tag in the spotlight.

Semantic tag (like tag::table_) now defines the actual mapping process
and defaulting process of option fetching. This lead to the upcoming
change of itnerface in container and related systems.

Unit Tests on options have been streamlined and completed.
Adapt container and container tests to new container interface

container now exposes their semantic through their type. This is
required so semantic of data are not tied to some implicit
settings requiring strange hoops to be set and retrieved.
Make table_ conformant to new semantic concept
Complete deduce_semantic behavior and tests
Fix friend declaration