Strange type mapping for ffi

[KaruroChori]

By the way, there is also something quite suspicious happening @ https://github.com/saghul/txiki.js/blob/master/src/js/stdlib/ffi/ffi.js

    [ types.uint32, [ 'uint32_t', 'signed long long', 'signed long long int', 'long long', 'long long int' ] ],

Does not seems right, unless there are strange reasons behind this choice.

Originally posted by @KaruroChori in #506 (comment)

[lal12]

Hmm, yes. That definitely does not seem to be correct.

[KaruroChori]

Thanks for the fixes