neutrino: add a prototype of a lua plugin interface

this is just for preliminary tests, not yet really usable
for anything useful
luainstance: the name is "Lua", not "LUA"
luainstance: add simple GetInput() method

use like this in the lua script:
--
RC_home = 174
local n = neutrino()
repeat msg, data = m:GetInput(1000) until msg == RC_home
luainstance: add minimal error reporting
luainstance: show errors from loadfile()
luainstance: export variables as tables

This exports arrays FONT_TYPE_foo as FONT['foo'], COL_bar als COL['bar']
and SCREEN_OFF_a as SCREEN['OFF_a'] instead of lots of single variables.

Later these could also be made dynamic if the need arises.
luainstance: also export RCInput constants
luainstance: export FontHeight to Lua scripts
luainstance: dynamic values are not static
luainstance: allow rounded corners in PaintBox
luainstance: allow any color for PaintBox, disable debug
luainstance: work around a signed/unsigned problem on ppc
luainstance: export customcolor.h colors, too
luainstance: remove utf8 parameter from RenderString, add center

Everybody should always be using utf8 anyway, so remove the "utf8"
parameter from RenderString and replace it with a "center" parameter
which centers the string horizontally in its box.

new usage:
   RenderString(font, text, x, y, color, boxwidth, boxheight, center)
defaults:
   color = COL_MENUCONTENT, boxwidth = window's width minus x
   boxheight = 0, center = 0
luainstance: return render width from RenderString

Return the string's renderwidth from RenderString. If boxh is < 0
then the string is not rendered and only the width is determined.
handling of luaposix for dynamic environment
configure: try to autodetect lualib
luainstance: support new text coloring scheme

Signed-off-by: Stefan Seyfried <seife@tuxbox-git.slipkontur.de>
Preparing the menu classes for Lua Part #1

- Remove CNonLocalizedMenuSeparator
- Add overloaded function CMenuSeparator for non local
  THX Martii
Preparing the menu classes for Lua Part #2

- Remove CMenuForwarderNonLocalized
- Add overloaded function CMenuForwarder for non local
  THX Martii