update the aurelius wiki

[schlichtanders]

the aurelius wiki is apparently outdated and doesn't include the syntax changes mentioned in the R package on CRAN https://cran.r-project.org/web/packages/aurelius/vignettes/migration-to-new-syntax.html

(just starting reading about PFA and while the documentation seems better than for PMML regarding how to create your own models, this outdatedness nevertheless looks like a reason to not use PFA)