2 - check for complete support for 0.100 (compiles; existing tests pass)
5 - support DEL as vararg
6 - support MLLEN and MSCARD
13 - sort lexicographically
14 - sort with pattern and weights
17 - benchmarking "test" app
21 - make all string literals constants so they can be easily changed
22 - add conveniences that store a std::set in its entirety (same for std::list, std::vector)