Name shaders foz/hash/ExecutableName

We're currently only considering one shader per foz file because we stick stuff in the hash based on the name for which we were only using the name of the .foz file which meant we only considered a single shader and it wasn't even guaranteed to be the same shader from both files. To fix these issues, we instead use .foz/hash/ExecutableName as the name so we get a complete name for the shader. This should also let us more easily identify the shaders in the output.