MDL-15537 - create oo attemptlib.php to hold shared code between attempt, summary and review.php
MDL-15541 - Refactor starting a new attempt into a new file startattempt.php
MDL-15538 - Rework attempt.php to use attemptlib.php
* Javadoc comments for most of the code I committed on Friday.
* Implement the get_question_status method.
* Along the way, refactor duplicated logic between two of the question types, questionlib, and the new code - removing inconsistency while doing so.
Part one, a first cut of a summary page, along with some classes that will allow me to eliminate more duplicated code between the new page, attempt.php and review.php.