Parser chokes on vararg functions

[n1tehawk]

Currently, the parser is unable to handle vararg function declarations like e.g.

local function printf(...)
	print(string.format(...))
end

local function printf_alternative(fmt, ...)
	print(string.format(fmt, ...))
end

as it always expects identifiers in the argument list.

Pull request #1 is a first, incomplete attempt to fix this. I've submitted my solution in #2.

Regards, NiteHawk