CHANGES IN VERSION 1.0.0
------------------------
 - user can now supply her/his/its own colour vector to label the points
 - default is to now draw grid lines and only have left and bottom borders
 - when selectLab is not NULL, even variables that do not pass the thresholds
   are now labelled along with those that do, even when DrawConnectors is
   either TRUE or FALSE.
 - correctly catches non-numeric x and / or y variables, and throws error.
 - the function now tolerates P values of 0 (zero) and replaces these with the
   lowest possible double value, given a user's specific computer architecture
   and R version.
