Persist weapon fire mode & grenade launcher data

[Tosox]

Related to issue #401

[damoldavskiy]

Just wanted to say, a new attachment system is being worked on, so at some point scope attaching/detaching won't cause weapon respawning and all script-side logic related to it is going to become obsolete. I'd suggest to wait, or at least limit the fix to sensitive state parameters, like loaded shell in GL.

[Tosox]

Thanks for pointing this out, but yes, I am aware that after we get the new attachment system this will be barely relevant anymore. But it will still fix alife_clone_weapon calls in the future, when for example addons use this function.