Script tests re-added, all tests can run under gdb

Also fixed a minor bug with printing, and removed the ability to
configure the parser.

Added and updated QUICKSTART.md as a quick way to get people started.

There's some broken scripts under 'scripts/' that require functions to
work properly.

tests/scripts/test_control_flow.toy

@@ -0,0 +1,9 @@
+//these are allowed
+/* EMPTY */;
+if (true) { }
+if (true) pass;
+
+
+//these are not allowed
+// if (true) /* EMPTY */;
+