Parsing exprs, enum_decls, Introduce intern table, symbol table

os.h

@@ -0,0 +1,9 @@
+
+typedef struct OS_Memory{
+  void *data;
+  SizeU commit;
+  SizeU reserve;
+}OS_Memory;
+
+function OS_Memory os_reserve(SizeU size);
+function void os_commit(OS_Memory *m, SizeU size);