#' Check if the specified R packages are present in the computer and import them into the working environment
#' Check if the specified R packages are present in the computer and import them into the working environment
#' @param req.package Character vector of package names to import
#' @param req.package Character vector of package names to import
#' @param load Logical. Load the package into the environement (using library())? Interesting if packages are not in default folders or for checking the functions names of packages using search()
#' @param load Logical. Load the package into the environment (using library())? Interesting if packages are not in default folders or for checking the functions names of packages using search()
#' @param lib.path Optional character vector specifying the absolute pathways of the directories containing some of the listed packages in the req.package argument, if not in the default directories. Ignored if NULL
#' @param lib.path Optional character vector specifying the absolute pathways of the directories containing some of the listed packages in the req.package argument, if not in the default directories. Ignored if NULL