kasparm

Initial code modifications are here: https://github.com/kasparm/most/tree/dcline-in-most https://github.com/kasparm/matpower/tree/dcline-in-most I am working on dclinecost and adding a test. Comments are welcome.

Yes, that is right. The current implementation I am working on requires that the user invokes the callbacks by hand as you described above(`ext2int()` / `int2ext()`). Thank you for pointing...