Commit pre enabling CTCE pass (which is quite slow, but does work). Had to add walking through cast nodes for finding variables to close over. Also had to remove the static in front of functions to prevent gcc compiling it so that it segfaults (doesn't segfault if compiled with clang, but wanted to make sure.)

tests/test_ctce_pass.expected_results

@@ -0,0 +1 @@
+more than 10000 nodes!