Refactor a load of initialisation into RAII-controlled types
Refactor a load of initialisation into RAII-controlled types

There is a residual problem with destruction, with a crash after
all destruction has taken place.  valgrind reports one problem which
looks like an nVidia driver oddity, then the next is in vkDestroyInstance.

StrayLightning/aeolius,StrayLightning/aeolius,StrayLightning/aeolius