bug fixes for show/hide process buffer

+ Show Process Buffer will create a Lua process if one doesn't exist

+ Hide process buffer works correctly when buffer gets killed or is nil
  (delete-windows-on nil) could be executed before, which will do
  the wrong thing
Merge remote-tracking branch 'upstream/master'
fixed up tests && improved lua-kill-process
Merge remote-tracking branch 'upstream/master'
Fixed broken local variable assignments
Merge pull request #79 from j-fu/master

Fixed broken local variable assignments for Emacs 24.3
Provide lua--setq-local fallback macro for pre-24.3
Use syntax-propertize-function if it is available

font-lock-syntactic-keywords aren't considered if font-lock-mode is off.
Drop pre-Emacs23 support macros
Merge pull request #69 from atomontage/master

Bug fixes for show/hide process buffer
Move credits to AUTHORS, cleanup Commentary section a bit