Add more Zig test programs.

tests/hellozig/pointers.zig

@@ -0,0 +1,26 @@
+const std = @import("std");
+const print = std.debug.print;
+
+const Single = *bool;
+
+const Many = [*]bool;
+
+const Null = ?*bool;
+
+pub fn main() !void {
+
+    var v = false;
+    const ptr: *bool = &v;
+    print("pointer: {}\n", .{ptr});
+
+    ptr.* = true;
+    print("value: {}\n", .{ptr.*});
+
+    const const_ptr: *bool = &v;
+    const_ptr.* = false;
+
+    const cf = false;
+    const ct = true;
+    var ptr_to_const: *const bool = &cf;
+    ptr_to_const = &ct;
+}