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'
Add lua-remove-syntax-table-property to syntactic keywords

Sometimes font-lock doesn't unfontify the region when applying syntactic
keywords and that broke multiline literal recognition.
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
Mention xristos in AUTHORS
lua-send-region: send extra printline

This avoids putting interpreter output onto the prompt line.
Redo handling of "stdin:N" in tracebacks

The regexp that disabled highlighting of "stdin:N" turned out to be
overly magical (unstable, any change in it caused breakage).

This change enables highlighting back and adds advices around
compilation-mode functions to ensure minimum inconvenience: now any
"stdin:N:" message at line L points to line L of REPL buffer.
SMIE indentation refactoring: initial attempt
lua-smie: use syntax setup from lua-mode