Start naming changes in preparation for turning index experiments into production quality code. Delete the initial index_set.hpp and index_common.hpp attempts as these were blind alleys replaced by the index.hpp code.
Create the files for index sets, maps, and their base classes. Rename index_test.cpp to index_unit_test.cpp
Remove the index_test VC++ project.
Initial content commit, distributing the experimental code from index.hpp to index_set.hpp and index_bases.cpp. No attempt to compile yet.
Unstable work in progress.
The combined traits were too hard to use, so have been removed. The removal was done manually, rather than using git to revert the changes, so that several fixes and other improvements could be retained.
Add explicit destructor for maps and sets. In theory the base class destructor should be sufficient, but in practice VC++ 2012 is failing under IDE testing (but only if a compile was run) without the derived class destructor.