This will check if you have the
Vulkan SDK installed by checking
if the VULKAN_SDK env var is set.
If it’s set then nothing will happen.
If it is not set then it will download
the latest SDK from lunarg.com and install
it at home/.vulkan_sdk.
It will then set the required environmnet
variables.
You can install silently or with a message.
Use check_or_install(Default::default())
for an install with a default message