Support more dtypes by array, dict, object bottom docks

[don-tnowe]

For generics, it only allows int, float, String and "try guess the type". For single-type collections, it should know the type, but only limits to these 4.

You'll need to write the literal correctly (quotes, constructor etc.) to insert.

• StringName (currently: must add quotes)
• Color (writing the hex code; currently: must add Color() constructor)