imports phylogenetic trees from treebase. internal function
get_nex(
  query,
  max_trees = "last()",
  returns = "tree",
  curl = getCurlHandle(),
  verbose = TRUE,
  pause1 = 1,
  pause2 = 1,
  attempts = 5,
  only_metadata = FALSE
)A list object containing all the trees matching the search (of class phylo)
: a phylows formatted search, see https://sourceforge.net/apps/mediawiki/treebase/index.php?title=API
limits the number of trees returned should be kept.
should return the tree object or the matrix (of sequences)
the handle to the curl
a logical indicating if output should be printed to screen
number of seconds to hesitate between requests
number of seconds to hesitate between individual files
number of attempts to access a particular resource