Give better symbol names to generated tokens

This should make debugging easier

src/compiler/util/string_helpers.cpp

@@ -0,0 +1,24 @@
+#include "compiler/util/string_helpers.h"
+
+namespace tree_sitter {
+    using std::string;
+    
+    namespace util {
+        void str_replace(string *input, const string &search, const string &replace) {
+            size_t pos = 0;
+            while (1) {
+                pos = input->find(search, pos);
+                if (pos == string::npos) break;
+                input->erase(pos, search.length());
+                input->insert(pos, replace);
+                pos += replace.length();
+            }
+        }
+        
+        string escape_string(string input) {
+            str_replace(&input, "\"", "\\\"");
+            str_replace(&input, "\n", "\\n");
+            return input;
+        }
+    }
+}