Signed-off-by: Craig Robbins <kde.psych@gmail.com>

According to doc/lua_api.txt if paramtype2 == "facedir" the two least significant bits of parm2 orient the texture around the axis. For dirs1 (looking at a wall) these would be 0, 1, 2, 3 and for dirs2 (looking at the ceiling) 2, 1, 0, 3

Also shortens some related code and adds more parameters to string.split.

Changes:
  * Indentation with tabs by default.
  * Array keys dumped without "[i] = " prefix.
  * String keys that are valid identifiers aren't enclosed in '[""]'.
  * Basic support for multiple references (as specified in the comment).

Changes:
  * Add comments to explain the dumping code
  * Add support for dumping values of any type (as '<' <type> '>')
  * Add support for tables as keys in dump2()
  * Make dump2() return it's result (like dump()) rather than printing it
  * Simplify and optimize function serialization via serialize()

Add engine.gettext() and remove gettext() calls in guiFormspecMenu.cpp