Fixed issue with accessing a WithStatement context from inside a nested function. see mini/with2.d

Renamed some LLVM uses of ::create statics to ::Create , lower case ones will be deprecated soon.

tests/mini/with2.d

@@ -0,0 +1,17 @@
+struct bar {
+    int bar;
+}
+
+void main() {
+    bar Bar;
+    with (Bar)
+    {
+        assert(Bar.bar == 0);
+        void test()
+        {
+            bar ++;
+        }
+        test();
+    }
+    assert(Bar.bar == 1);
+}