Support multiple PipelineStates in Renderer

Support multiple PipelineStates in Renderer

In the Vulkan backend it can be beneficial to keep separate pipeline
states and avoid having to repeatedly compute hashes and look them up
from the cache.  The downside is that every time the used state object
changes, shader data has to be reapplied.  But it's likely this would
be necessary anyway due to different shader or data being used.