Create a list of the available SRTM files on the server using
        HTTP file transfer protocol (rather than ftp).
        30may2010  GJ ORIGINAL VERSION

def createFileListHTTP(self):
        """Create a list of the available SRTM files on the server using
        HTTP file transfer protocol (rather than ftp).
        30may2010  GJ ORIGINAL VERSION
        """
        mp_util.child_close_fds()
        if self.debug:
            print("Connecting to %s" % self.server, self.directory)
        try:
            data = self.getURIWithRedirect(self.directory)
        except Exception:
            return
        parser = parseHTMLDirectoryListing()
        parser.feed(data)
        continents = parser.getDirListing()
        if self.debug:
            print('continents: ', continents)

        for continent in continents:
            if not continent[0].isalpha() or continent.startswith('README'):
                continue
            if self.debug:
                print("Downloading file list for: ", continent)
            url = "%s%s" % (self.directory,continent)
            if self.debug:
                print("fetching %s" % url)
            try:
                data = self.getURIWithRedirect(url)
            except Exception as ex:
                print("Failed to download %s : %s" % (url, ex))
                continue
            parser = parseHTMLDirectoryListing()
            parser.feed(data)
            files = parser.getDirListing()

            for filename in files:
                self.filelist[self.parseFilename(filename)] = (
                            continent, filename)

            '''print(self.filelist)'''
        # Add meta info
        self.filelist["server"] = self.server
        self.filelist["directory"] = self.directory
        tmpname = self.filelist_file + ".tmp"
        with open(tmpname , 'wb') as output:
            pickle.dump(self.filelist, output)
            output.close()
            try:
                os.unlink(self.filelist_file)
            except Exception:
                pass
            try:
                os.rename(tmpname, self.filelist_file)
            except Exception:
                pass
        if self.debug:
            print("created file list with %u entries" % len(self.filelist))