Various 2d Images Todo

[Guac0]

Literally nothing except the insignias have their 2d arsenal/inventory pictures working. All have either a placeholder texture, or, in cases where the placeholder icon doesn't work (arsenal and inventory for guns and helmets), a default picture. There are two phases to fixing this:

1. Creating placeholder icons for guns and helmets that will not throw errors like the default placeholder icon does due to their icons being sized differently. This should be fairly easy and would be a good first job for someone to do.
2. Creating final icons for each individual gun and helmet. This is a tad advanced, and can be delayed if we get the revised placeholders working fast.