Fixes for timelines that are set from with(other){} type blocks

Essentially, using the following would lead to an error:
```
with(other) {
  timeline_index = tline_0;
}
```

There were a few problems behind this. First, since "other" didn't know that tline_0 was a valid index, it would silently fail to update that timeline. (This is a bug in the parser that applies to with(other) in general with I intend to fix at some point in the future.) There are some cases that we will never be able to tag correctly; for example, "with(1000001){}". So, I wrote a "default:" case in all timeline lookup switches that would call the parent class's lookup method (the parent class contains a definitive lookup of all timelines).

Following this, timelines would trigger but glitched like crazy. In fact, it looked a lot like (https://github.com/enigma-dev/enigma-dev/pull/781), and was in fact the same bug --except applied to timelines instead of global scripts. This only happens when the default case is called. So, I applied the same fix as in the linked bug.

This fixes a few glitches with Iji's timeline-driven cutscenes (not the intro).