Avoid zero-initialization of memory areas for for more efficiency

[mdilai]

Second version of #3324. Using plain "new"s instead of std::make_unique_for_overwrite and only for player avatars and weapon icons as it give measurable performance impact. Some benchmark times: Caching new avatar (median):

• make_unique: 0.0001175s
• new: 0.000057s

Loading weapon icons is hard to measure but anyway its a up to 9 unnecessary operations per frame on my PC.

[aoqia194]

Very nice.