starting v2.0a49x
Minor (untested so far) safety tweaks to Foundation/Execution/ProcessRunner for POSIX.
Fix (hopefully) dangerous deadlock bug with ProcessRunner(). FORK copies
everything, including mutexes that could be locked! - and so we CAN deadlock
because some thread somewhere had locked a string class mutex before our fork, and
when we try todo stuff in the child, we lose badly! Hopefully fixed (POSIX ONLY).
execpe const kookiness
v2.0a49