several pfk_environ fixes
several pfk_environ fixes

- make sure every msg has NOTE: or ERROR: on it
- ERROR sent to stderr always
- search directories backwards, not forwards, allowing subdirs to
  override their parents.
- if pfk_environ is removed between enter and leave, don't crash
  'cd()' function

flipk/pfkutils,flipk/pfkutils,flipk/pfkutils,flipk/pfkutils,flipk/pfkutils,flipk/pfkutils,flipk/pfkutils