Ensure child process doesn't attempt to reap itself
Don't close file handles on DESTROY

There is no point at this stage as no-one cares about the state of the
object or its handles, and they will close on their own (or be closed
by the operating system) later.
Better detection & tests for non-executable target
Changes update
Use POSIX::_exit after calling CODEref to prevent DESTROY actions
Remove unecessary warnings during DESTROY/END blocks
VERSION 0.81.4
Fix broken changelog