Tidy: + "other" files to .pro, fix space/punct in LUA messages, spell in commnt.

The LUA and documentation files were not listed in the mac_src.pro and src.pro
files but adding them in makes access in IDE easier and may help installers.
As a result of the former a trivial spelling mistake and some tab/space
indentation mismatches spotted!

Missing spaces at end of some of the LUA error messages made following text
from elsewhere in LUA system not append nicely, some punctuation makes it
visually better.

Signed-off-by: Stephen Lyons <slysven@virginmedia.com>