C-bowman/inference-tools: 0.4.5 Release

Added a new class ParallelTempering to the inference.mcmc module which runs the 'parallel tempering' MCMC algorithm.

ParallelTempering uses Python's multiprocessing module to create separate, dedicated processes for each Markov-chain object involved in the parallel tempering algorithm, allowing the necessary computations for each object to take place in parallel if multiple CPU threads are available.