dec_two                 Function that returns numeric values with 2
                        decimal numbers.
getDatasetFeaturesFromGEOcode
                        Function that reads in the GEO code of a
                        dataset, and returns the complete gene
                        expression dataframe by printing its features
                        (if requested).
getGeneExpressionFromGEO
                        Function that reads in the GEO code of a
                        dataset, and returns the gene expression
                        dataframe.
readUrl                 Function that reads in a URL to check and
                        verifies if it exists (function written by
                        Janko Thyson @rappster and taken from
                        https://stackoverflow.com/a/12195574 )
