Feature: RPG dialog boxes

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Many RPGs use a similar style of dialog box. It generally works as follows:

1. Clear the box and store the string to display
2. Wait for a delay period to pass, usually a fraction of a second
3. Display a new glyph after any previously shown
4. If there glyphs left to show, go back to step 2
5. Wait for the player input
6. If there are further strings to display, select the next one and go to step 1.
7. Close the dialog box

Examples include:

• The Pokemon series (0:30, time offset included in link)
• The Final Fantasy series (6:15, time offset included in link)

It could be implemented by doing the following:

1. Subclass one of the built-in UI widgets , such as arcade.gui.UILabel
2. Use one of the built-in Kenney pixel fonts as the font
3. Add an on_update method that takes a float, delta_time. This method will increment tracking for the character display functionality.