MDL-27490 Implement a manage question behaviours admin page

MDL-27490 Implement a manage question behaviours admin page

While doing this, I found various bugs in the manages question types admin page, and so fixed them, and updated the code
there to use $OUTPUT and html_writer.

AMOS BEGIN
 MOV [cannotdeletemissingqtype,admin],[cannotdeletemissingqtype,question]
 MOV [cannotdeleteqtypeinuse,admin],[cannotdeleteqtypeinuse,question]
 MOV [cannotdeleteqtypeneeded,admin],[cannotdeleteqtypeneeded,question]
 MOV [deleteqtypeareyousure,admin],[deleteqtypeareyousure,question]
 MOV [deleteqtypeareyousuremessage,admin],[deleteqtypeareyousuremessage,question]
 MOV [deletingqtype,admin],[deletingqtype,question]
 MOV [numquestions,admin],[numquestions,question]
 MOV [numquestionsandhidden,admin],[numquestionsandhidden,question]
 MOV [qtypedeletefiles,admin],[qtypedeletefiles,question]
 MOV [uninstallqtype,admin],[uninstallqtype,question]
AMOS END