bigvim.bat makes 7.3.834 break Ruby 1.9.x support

People complained that my recent build of Vim no longer worked with Ruby. I reproduced the behaviour. I checked the recent Ruby-related patches, and found out that reverting 7.3.834 made it work again.

Obviously, this part is problematic:

*** 344,349 ****
--- 346,362 ----
  {
      return dll_rb_int2big(x);
  }
+ #if defined(DYNAMIC_RUBY_VER) && DYNAMIC_RUBY_VER >= 20
+ VALUE
+ rb_float_new_in_heap(double d)
+ {
+     return dll_rb_float_new(d);
+ }
+ unsigned long rb_num2ulong(VALUE x)
+ {
+     return (long)RSHIFT((SIGNED_VALUE)(x),1);
+ }
+