Support more xterm/VT100 control characters

### Problem

I use some VT100 control characters in my scripts. I've found that Elementary Terminal seems to ignore them.

[`bigtext`](https://github.com/colindean/hejmo/blob/master/scripts/bigtext):

```bash
#!/bin/sh
text="${*}"
printf "\033#3%s\n" "${text}"
printf "\033#4%s\n" "${text}"
printf "\033#5"
```

```
$ bigtext this should be big
this should be big
this should be big
```


### Proposal

Support xterm/VT100 control characters

One document on them:

https://invisible-island.net/xterm/ctlseqs/ctlseqs.html

### Prior Art (Optional)

xterm and Apple Terminal support this, but iterm2, gnome-terminal, terminator, and alacritty do not. I only tested those.