v1.0.2 Handle -math.MaxFloat64

See the reference commit: f11aaf8#diff-7b1acceb6c69e828c14f395f75251c426b8cb94f00173ce2d19d1c1cdf66c69eR116

1. While finding most probable state we should pick not just the first element in array, but first existing transition probablity
2. Should not do math stuff when -math.MaxFloat64 happens

v1.0.1 Same logic for EvalPathLogProbabilities and EvalPath

Just made EvalPathLogProbabilities and EvalPath functions to look familiar and fixed some negligible errors in EvalPath (in evaluating max probability for not normalized values)
Change notation a bit according to Wikipedia - https://en.wikipedia.org/wiki/Viterbi_algorithm#Pseudocode