YAXT

This release addresses minor bugs in the internal derived data type packing/unpacking where

• MPI_FLOAT_INT might lead to a SIGBUS on some architectures.
• Reference tests for 0-size datatypes incorrectly use a buffer of size 0, but the MPI spec requires a buffer of the size provided by MPI_Pack_size.

Also, it includes some improvements for xt_idxsection and xt_idxstripes and a few refactorings that were release ready.

The internal derived data type packing/unpacking can now be disabled with the configure switch --disable-xt-ddt-exchanger.