Multiple small features & fixes

[Jowan-Spooner]

• color names and codes on default background (Allow to enter color codes and names for default background scene  #1374)
• fix autopauses and remove hide_textbox_when_empty setting
• support modifiers (br, random selection) in choice texts - fixes Supporting line breaks within choice boxes #593
• fix for When providing a folder path to Typing Sounds, Dialogic doesn't utilize every sound in that folder #1749

[CakeVR]

I found the following problem, which is a warning for people testing this:

When I added an Auto-Pause, Dialogic will report:
Invalid get index 'text_speed' (on base: 'Node (subsystem_settings.gd)').

Reproduction of this bug:

1. Add an arbitrary string - e.g. "." - with an arbitrary time delay.
2. Disable Absolute auto-pause timers.
3. Run a sentence containing ".".

This bug gets fixed by my pull request: #1755

[Jowan-Spooner]

When I added an Auto-Pause, Dialogic will report:
Invalid get index 'text_speed' (on base: 'Node (subsystem_settings.gd)').

@CakeVR I pushed a fix for this. When we merge the autoadvance PR we can choose your fix or this one, idc.