Adding transitionStore optimization back to ByteState

[jonessha]

Description of changes:

I removed transitionStore in favor of ByteMap when adding wildcard matching.

transitionStore was an Object that could be null if 0 transitions were present, a simple object if 1 transition was present, or a Map if 2 transitions were present. I had replaced this with the new class ByteMap, which greatly simplified the code. However, it is not as memory efficient to always allocate a ByteMap. Hence, I am re-introducing transitionStore, which again, can be null, a simple object, or a ByteMap (for 2+ transitions). The downside of this is it does bloat the code quite a bit.

Through some crude testing, I expect this to replace nearly 50% of ByteMaps with the simple object SingleByteTransitionEntry. In this case (1 transition), my back-of-the-napkin math suggests ByteMap would require 96 bytes and SingleByteTransitionEntry would require 8 bytes, a 12x difference. So this is, on average, a 44 bytes saving for each ByteState.

I have run this in a high volume production environment and have observed a modest improvement in GC activity (maybe a 10% reduction).

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