Enable array RAII and provide uninit(-), a uNoCtor equivalent.
Enable construction/destruction of "new" CFA array elements,
which was previously deactivated to avoid a compiler performance issue.
The enabled RAII steps more carefully around the performance issue.
Provide uninit(-), with tests covering the typical use case:
struct Foo;
void ?{}( Foo & this, int i ) { printf( "ctor at %d\n", i ); }
uninit(Foo) a[10]; no prints
for (i; 10) (a[i]){ i }; prints
array(uninit(Foo), 10) b; no prints
for (i; 10) (b[i]){ i }; prints
