Add set_value() function for LineEdits, ColorPickers, ColorPickerButtons, Selects etc.

[Maximinodotpy]

In Godot, there are several types of input fields, and each one has a different property to the value correlating to it.

For example, LineEdit has text and ColorPicker has color.

And I think it would be good if there were a function for all of these Nodes to set and get these values, without the need to know what the property name is.