[WIP] Add toggle to allow Fungus to run on unscaled time. Take 2.

[esklarski]

Description

These changes enable Fungus to run while Time.timeScale == 0.
What is the current behavior?

If Time.timeScale is set to 0 Fungus is paused and uninteractable
What is the new behavior?

I made these changes, sans switch, for a project where I used Fungus for all the menus. I needed to pause 3d gameplay but have a character come up to act as the pause screen menu.

Behaviour Now:

Fungus remains interactable while Time.timeScale == 0

Important Notes

My change require modifcations or additions to documentation
My change modifies the runtime execution/behaviour of existing Fungus Features. e.g., Say, Menus, Portraits, etc.
My change adds demos to FungusExamples -- coming soon

Other information

Still a work in progress:

Need advising on location of behaviour switch (currently FungusManager.cs)

[esklarski]

Here's a much cleaner version than my original. I'll add a demo scene when I get a bit more time.