Airblast Rework proposal

[Drand0r]

Changing airblast from requiring damage to a simple timer would not only make airblast easier to balance, but also allow it to act like a secondary ability for pyro primaries, allowing them to serve different purposes and give players a reason to use neglected flamethrowers like Degreaser and Backburner.

e.g. Stock being the most basic can have the lowest cooldown airblast (15 seconds)
Dragon's Fury already being unique and has a decreased repressurization rate can have a longer cooldown (20-25 seconds)

As for the Degreaser and Backburner, they need more than just their base stats to stand out as primaries worth using.
Degreaser: +200% airblast force, 30-40 second cooldown. This keeps the Degreasers' niche as a supportive flamethrower, allowing it to forcibly disengage Hale to save teammates or just push them off the map, with a high cooldown to stop it from making a pyro impossible to catch.
Backburner: On a successful airblast, Axtinguisher-like expunge of all afterburn, dealing damage equal to the amount of afterburn damage remaining (not sure how easy this would be to make), 20-25 second cooldown. Gives the Backburner an extra source of burst damage almost like a combo-finisher, focusing on its offensive stats.

[FortyTwoFortyTwo]

Lots of suggestion done in #332. Backburner remains unchanged, but still up for possible change