MCMC data changes

More data is stored from MCMC now and the process is simpler making it easier to store other information in the future. One of the biggest changes is during the bounds modification step the previous bounds, new bounds and 5% and 95% values are written into mcmc.h5

The system also automatically uses these bounds if a prior is used in a simulation. Since the MCMC interface is pretty stable now it makes sense to make more parts of it automatic.

Another thing that has changed which gives a decent speedup is the sampler is no longer reset at the end of burn in so the random number generator and population are kept intact since this represents the burned in state.

Other minor things include a new version.py file that populates a lot of version, author, email, license etc information in the code. This also means that CADETMatch.version works now.