updated example script and renamed some functions as well
fixed bug in printtable cursor position if greater than maxlines for the
screen would reset to item 1
now we move the list start and select it
(and try to center it on the screen)
fixed a few bugs in the add_menu code
Change-Id: I01dead0481ef2e925af8b4cc6c14e36c2859dbba
allows menus + submenus + context menus all with simple tables
menu_t which is a table of strings
func_t which are the corresponding functions to go with those strings
see lua_scripts/submenu_demo.lua
Change-Id: I907b74b4abef0ecbe49f181d0ced6e6d20e94de5