Clarify auxiliary variable types

• Move https://archives.dynare.org/DynareWiki/AuxiliaryVariables to new Wiki
• According to https://git.dynare.org/Dynare/dynare/-/blob/master/matlab/isauxiliary.m there are more than the 6 documented types
• Check https://git.dynare.org/Dynare/dynare/-/blob/master/matlab/disp_dr.m for consistency (type 10 is missing)
• Check whether type >8 still actually arises