Alas, MVFF and MVT can't round up alignment because they need to support buffered allocation.
Remove comment from mpscmv2.h -- it's obsolete (no such thing as mps_count_t) and anyway documentation is now in the manual.
Assertion about alignment in MVFree might catch some errors at an earlier and more comprehensible point in the code.
Update the stress test cases (apss, mpmss, sacss) so that they test different alignments.
MVFF debug now supports alloc/free of large objects (by exposing and covering all segments which the object overlaps)