Reusable Functions

Pulling some more functions out of the Blackboard Import project into separate include files, for reuse by other projects (specifically the page-generator functions, which had been embedded in canvas-api.inc.php, where they didn't really, logically belong and the functions for working with session-based temporary directories).

Also, made callCanvasApi() more forgiving about the (now-optional) $data parameter.

Signed-off-by: Seth Battis <SethBattis@stmarksschool.org>
Archive Discussions

A first, quick pass at a tool to archive discussions. Initially meant just to archive discussions out of a group, for potential reimport into a course, it's written so that it should be able to archive discussions out of a course, group or collection.

N.B. Because the group that I was archiving had less than 50 discussions, I didn't bother to deal with the pagination of Canvas' JSON responses proactively!

Signed-off-by: Seth Battis <SethBattis@stmarksschool.org>