Course overview block should remember number of courses per page

The blocks should remember the "per page" option the user has selected in their paged content widgets so that when the page is reloaded the same number of items is rendered again rather than being reset to the default value.

E.g. the course overview block has options to view 12, 24 or 48 courses per page but it doesn't remember which option the user selected and will default back to 12 on each page load.