756 – IFTI for tuples only works if tuple parameter is last

The spec does not seem to require that tuple parameters are the last parameter in the list, but this doesn't work:
void foo(U...)(int t, U u) { }
void bar(U...)(U u, int t) { }
void main()
{
 foo(1, 2, 3); // Ok, IFTI works
 bar(1, 2, 3); // error: cannot deduce template function from argument types (int,int,int)
 bar!(int, int)(1, 2, 3); // Ok.
}

This seems to be a root cause for quite a few recent bug reports.
Added to DStress as
http://dstress.kuehne.cn/run/t/tuple_13_A.d
http://dstress.kuehne.cn/run/t/tuple_13_B.d
http://dstress.kuehne.cn/run/t/tuple_13_C.d 

Please remember to assign keywords to bug reports. To everybody reading this: Please look through issues you've reported and check for missing keywords.

Fixed dmd 1.028 and 2.012