Ancestral state reconstruction for multiple MRCAs with datatype-awareness

[Anaphory]

I have written and tested an AncestralStatesLogger extension, which allows the reconstruction at multiple MRCA nodes, each specified by a taxonset, and which logs the original representation of the value instead of the internal one (eg. covarion logs as 01ab instead of 0123 – The code for that was taken from the AncestralStateTreeLikelihood class in beast-classics).

That class should be backward compatible with AncestralStateLogger and I would be happy to create a pull-request to it for this directory, if you like.

[Anaphory]

Do you want that contribution here, or what would be a good place to provide that functionality to the wider BEAST users community?