If <min-reserved-size> is less than <max-heap-size>, the code will
still assume that only <min-reserved-size> bytes are accessible and
will trap even if the runtime could allocate more..
So, `max` should always be <= `min`. Naming options is hard.
However:
- wasmer seems to have issues with signals, causing some tests to fail
- lucet's --dir option doesn't seem to work with relative paths
These are temporary limitations, that are likely to be fixed soon.