Increase speed of trait evolution functions (xxx_discrete and xxx_continuous)

[gijsbertwerner]

function

Trait evolution / ancestral state reconstruction functions xxx_discrete and xxx_continuous.

Problem

Underlying functions from the geiger package are relatively slow, limiting the extent to which it's feasible to use them on larger phylogenies.

Potential solutions

For xxx_discrete, consider using the castor package instead: https://academic.oup.com/bioinformatics/article/34/6/1053/4582279.
For xxx_continuous, consider using Rphylopars instead: http://doi.wiley.com/10.1002/ece3.2837
Both should be orders of magnitude smaller.