Checks to see if the inputed path represents an existing file or directory.

        :param      relpath     | <str>
                    rsc         | <str>
                    useFilepath | <bool> or None

def exists(self, relpath, rsc=None, useFilepath=None):
        """
        Checks to see if the inputed path represents an existing file or directory.

        :param      relpath     | <str>
                    rsc         | <str>
                    useFilepath | <bool> or None
        """
        path = self.find(relpath, rsc, useFilepath)
        if path.startswith(':'):
            return QtCore.QResource(path).isValid()
        else:
            return os.path.exists(path)