VisualScript access to action value

### Describe the project you are working on

A game that is to be controlled with a gamepad and completely programmed using VisualScript.

### Describe the problem or limitation you are having in your project

Using VisualScript you can only access the information if a certain action is triggered, but not the exact value. This makes it almost unusable for joystick control.

### Describe the feature / enhancement and how it helps to overcome the problem or limitation

Add a float-output to the action-node in VisualScript that reflects the value of how much an action is triggered. This way you can easy integrate joystick-control or any other non-button-input in a expected way.

### Describe how your proposal will work, with code, pseudo-code, mock-ups, and/or diagrams

when user adds an action-node in VisualScript there will be a second output that gives a float-value of how much the choosen action is triggered.

### If this enhancement will not be used often, can it be worked around with a few lines of script?

Maybe by adding a GDScript but I'm not sure. But that's the point. Currently it is not possible only with VisualScript.

### Is there a reason why this should be core and not an add-on in the asset library?

The value for a input action should be accessible by standard since it is a basic feature for Joystick or gamepad input.