get_synergy_biomarkers_from_dir: Get synergy biomarkers from dir
In emba: Ensemble Boolean Model Biomarker Analysis

This function reads the synergy biomarker files inside the given directory and merges the results into a data.frame which it returns. This functions should be used when the synergy biomarker results are in separate files inside the directory given (see biomarkers.dir parameter).

get_synergy_biomarkers_from_dir(
  predicted.synergies,
  biomarkers.dir,
  models.dir = NULL,
  node.names = NULL
)

`predicted.synergies`	a character vector of the synergies (drug combination names) that were predicted by at least one of the models in the dataset.
`biomarkers.dir`	string. It specifies the full path name of the directory which holds the biomarker files (without the ending character /). The biomarker files must be formatted as: %drug.comb%_biomarkers_active or %drug.comb%_biomarkers_inhibited, where %drug.comb% is an element of the `predicted.synergies` vector.
`models.dir`	string. A directory with .gitsbe files/models. It's needed in order to call `get_node_names`.
`node.names`	a character vector which has the names of the nodes. If it's not NULL, then it will be used instead of the `models.dir` parameter. The `node.names` should include all the nodes that are reported as biomarkers in the biomarker files inside the `biomarkers.dir` directory. Note that the biomarker nodes in the files will be included in the returned `data.frame` object no matter the `node.names` specified. Default value: NULL.

a data.frame, whose columns represent the network nodes and the rows the predicted synergies. Possible values for each synergy-node element are either 1 (active state biomarker), -1 (inhibited state biomarker) or 0 (not a biomarker or the node is not at all present in the network or the drug combination is not a synergistic one).