Simplify creating extra BlockStorage::Buffer instances

[DavidZemon]

Creating a new BlockStorage::Buffer is way too difficult - currently, it takes three lines of code. It's great, because it doesn't require any dynamic memory allocation! But... difficult.

There needs to be a way to create a new instance of a buffer with a single line of code in such a way that the optimizer knows to exclude it if unused (therefore, no virtual method on BlockStorage)