enabled and tested basic functionality in lispworks
disabled loading of tests and examples
manually loading files as quickload exil doesn't work in LW yet
exil-utils:symbol-append now takes list of symbols (not by &rest)
  and an optional package, added eval-when
used in env-slots (reset-slots) and env-undo (with-saved-slots)
call to defenv and setenv in fe-base could need eval-when tweeking