compilation fixes for 2.065

- overload of findNextUDA is ambiguous

- __traits getFunctionAttributes isn't available
I don't really get your point. The [documentation](http://dlang.org/phobos/std_traits.html#functionAttributes) lists all enum members so the code should handle all of them. The fact that `@nogc` (and thus FA.nogc) was introduced after 2.065 is independent from the fact that we can use `__traits(getFunctionAttributes)` since 2.066, therefor it should be two static ifs.