Lang string fix and dot plus

There was a concatenation in the language string that stopped it working with the AMOS translation system.
Dot plus [.+] will allow anything but an empty string. If a gap is left empty this will not be displayed as the "correct answer". That was a change in renderer.php

Added admin link to make it easy to import example quesions

Version 1.9 of the Moodle Gapfill question type contributed by Marcus Green

In the admin interface there is now a link for importing the sample questions into a course.
This is a convenience way of doing a standard XML file question import.

Fixed issue where extended characters were not handled correctly. Have tested with
accented French and Spanish words, Cyrillic and Hindi. Thanks for the feedback to Eduardo Montesinos,
Mariapaola Cirelli, Ellen Spertus and others

Fixed issue where in interactive mode an incorrect answer would show empty braces (typically [])
where the answer in braces would have been shown in other modes.

Gapfill 1.8

v1.8

improved description of question type summary