Housekeeping (incl. message queue ns)
Fix: `with-replies*` now unstashes correctly after exceptions
Clean up (alpha) `with-replies` and parser design
Fix `eval*` exception behaviour
Finally (?) fix obscure parser/de-pipelining interaction issues
Mark `return` as alpha
Allow pipelined (non-throwing) parsing exceptions
Allow `return` parser wrapping
Wrap parser exceptions
Fix `with-replies` unstashing + parser interaction issue
Allow pipelined (non-throwing) Lua script exceptions