Implement player Pain, DeathSound and JoiningThink hooks

[fl0werD]

related to s1lentq/ReGameDLL_CS#607

[metita]

We can change your documentation to this one, seems more accurate, maybe some little changes can be made.

[metita]

Called when a player is reproducing pain sounds.

[metita]

"Called when a player reproduces pain sounds" is also valid and maybe more accurate to match _DeathSound one.

[metita]

Called when a player reproduces his death sound.

[metita]

Called when a player joins the server after connecting to it.

[fl0werD]

@StevenKal how to write description in english pretty?

[StevenKal]

Hehehe! Below is that I have set up as description for my ready upcoming module ReAPI v1.8.0 (in "reapi_const.inc"):

For pain:
Called when a client emits a "pain sound" on damage reception.

For DeathSound:
Called when a client emits a "death sound" on death.

For JoiningThink:
Called when a client "thinks for the join status" (permanently called on each call of "CBasePlayer::PreThink", and only when he is not assigned as specatator or not playing).

Feel free to copy & use them, no problem!

[StevenKal]

PS: I love the attempts previously made in order to find the right descriptions, like "Called when a player is reproducing pain sounds.", haha, this is like the client already heard pain sounds in his life, but he tries to reproduce/imitate them in-game! Hihi so funny!
And this one "Called when a player joins the server after connecting to it." is wrong, knowing this function is not only called on the beginning, but more than that, as a permanent "join rethink". But yes, it also does some job as with the intro camera.

So yeah, you should use mines if you do not want some vicious English people mocke at this like dumbs!