PS_PDF2ASCII - converts the input ps or pdf file to ASCII
    RESULT = PS_PDF2ASCII(FILENAME,DIRECTORY) converts the 
    input ps or pdf files to ASCII, using ghostscript's 
    utility 'ps2ascii' and moves the converted file into directory. 
    RESULT returns a success indicator, e.g. -2 if the input 
    file does not exist or has a wrong format, -1 if gs is not 
    installed or the path isn't set, 0 if 'ps2ascii' didn't 
    work properly, and 1 if the conversion was successful.
 
  Copyright 2011 Dimitrios Zeimpekis, Eugenia Maria Kontopoulou, 
                 Efstratios Gallopoulos