v5.5.0

AbstractMCMC v5.5.0

Diff since v5.4.0

This PR introduce two functions on sampler state, getparams and setparams!!. getparams allows retrieving the values of the parameters as a vector. setparams!! is the counter part of getparams.

This is part of the effort of making interaction between samplers easier. The motivation of this PR is that a "high-order" MCMC (e.g. Gibbs) can use getparams and setparams!! without having to know the exact type of the sampler state, thus paving way to a more generalized sampler design and implementation.

Merged pull requests:

• Add getparameters and setparameters!! (#86) (@torfjelde)
• Use copy instead of deepcopy for RNGs (#147) (@devmotion)