Started to setup for codebase validation tests.

Fleshed out initial version of AST::is_equal( AST* )

Setup the test directory with initial files for each major validation test.

test/ZPL-C/Readme.md

@@ -0,0 +1,18 @@
+# Test : ZPL-C Reconstruction
+
+***Note: This validation test has not been implemented yet.***
+
+Repo : https://github.com/zpl-c/zpl
+
+This is a AST reconstruction test of the ZPL-C library.
+
+Much of the dependency code used in gencpp is derived from the ZPL-C library.
+In the future I could directly generate that related code from the ZPL-C library.
+
+For now it just does the following:
+
+1. Download the ZPL-C library
+2. Grab all header and source file paths
+3. Generate an ast for each file and serialize it to a file called <name of file>.gen.<h/c>
+4. Reconstruct the ast from the generated file
+5. Compare the original ast to the reconstructed ast