New NOS system

[Fujiwara_Takumi]

I have a suggestion, that would remove any reason for using the bug I've reported viewtopic.php?f=7&t=22879. Instead of having a "while mousedown" nitrous on.

Make it "mouseclick" nitrous on while meter != 0 and stop it again with mouseclick (unless meter runs empty), this would eliminate the possibilites of activating the nos like before, because the NOS meter would tick, even if mouse isn't pressed down. Also it would remove the need to use the bug, at least in my case where I use it when I just don't want to have to push another button while cruising the city(which is kind of limiting, since my keyboard is PS/2 and sometimes I want to rest my right arm). So far I haven't seen a real use for it, but Webb saw the exploitability when I explained the effects of it. (eg. outrunning cops with constant nitrous etc.)

TL;DR Make it button press:ON, buttonpress:OFF system. Instead of the current Buttondown:ON.