util: Add Teal interface definition files
Enables writing code in Teal that is aware of the interfaces and
function prototypes in these other utils.
Could also be used to do type checks on Lua sources, but this tends to
have a lot of noise.
local record mod
sand : function (string, string) : string
sor : function (string, string) : string
sxor : function (string, string) : string
end
return mod