[svn r77] Fixed foreach on slice.

Fixed some nested function problems when accessing outer function parameters.
Major changes to handling of structs.
Initial support for unions.
Probably more...

test/union1.d

@@ -0,0 +1,15 @@
+module union1;
+
+pragma(LLVM_internal, "notypeinfo")
+union U
+{
+    float f;
+    int i;
+}
+
+void main()
+{
+    float f = 2;
+    U u = U(f);
+    assert(u.i == *cast(int*)&f);
+}