[PATCH] rearrange code in intl sub directory

[Chris Brannon]

> This moves intl/ to src/common and turns that directory into a library
> of common routines
> 
> This means that we can place other routines in this library also which
> are shared between the server and the modules.

Hi William,
If you look at the compiler warnings, you'll see a bunch of new
"implicit declaration" messages while compiling src/server/output.c.
So you need to add #include "fdsetconv.h" to that file.

I'm very sorry that I didn't spot it earlier today.

-- Chris