HARD vs SOFT assertions were never very well defined or supported.
Currently they just imply a level of functionality that isn't present;
it's better to remove them instead of expending the effort at this
point.
The annotations were never particularly robust, and weren't used in many
locations (or consistently). And we should be migrating to c++14
annotation syntax anyway. By focusing on writing them all locally we
will be a little more standards compliant, and the attributes should be
more visible.
