Mcmc reorder

Description

This is an attempt to solve #226 by sorting the parameters by name before swaps are done (and after new points are accepted into the chain either at init time or after proposals).

CC: @serguei.ossokine @vivien @bfarr

API Changes and Justification

Backwards Compatible Changes

• This change introduces no API changes
• This change adds new API calls

Backwards Incompatible Changes

• This change modifies an existing API
• This change removes an existing API

If any of the Backwards Incompatible check boxes are ticked please provide a justification why this change is necessary and why it needs to be done in a backwards incompatible way.

Review Status

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