v2.6.1

NEW FEATURES

• Added check_empty_beautier_folder to make sure
  no temporary files are created

MINOR IMPROVEMENTS

• None

BUG FIXES

• None

DEPRECATED AND DEFUNCT

• Removed all deprecated functions and function arguments
  that warn the user in the current CRAN version (v2.6)
• Internal functions clock_model_to_xml_prior_distr,
  tipdate_taxa_to_xml_tree, tree_priors_to_xml_operators
  work with infererence_model,
  deprecated other arguments
• Deprecated internal function clock_models_to_xml_prior_distr,
  redirect user to clock_model_to_xml_prior_distr
• Deprecated internal function tree_priors_to_xml_operators,
  redirect user to tree_prior_to_xml_operators
• Deprecated clock_models_to_xml_state,
  redirect user to clock_model_to_xml_state
• Deprecated clock_models_to_xml_operators,
  redirect user to clock_model_to_xml_operators
• Deprecated clock_models_to_xml_tracelog,
  redirect user to clock_model_to_xml_tracelog
• Deprecated mrca_priors_to_xml_tracelog,
  redirect user to mrca_prior_to_xml_tracelog
• Deprecated tree_models_to_xml_tracelog,
  redirect user to tree_model_to_tracelog_xml