Remember documents vs sitemap item selection - menu link picker

Acceptance Criteria

1. The default dropdown selection (when nothing is known about the user's previous selection) is 'Pages (sitemap items)' - not 'Documents'

2. If the user's previous selection is known the default setting is over-ruled and the selection shown is based on what the user had previously selected and which is stored

NOTE: the selection must only be stored when the user closes the link picker using 'OK', not when they close it with 'Cancel'.

3. The remembered/stored selection is shown in the menu link picker if the user:

a) logs out then back in again
b) refreshes the page
c) closes and re-opens the menu link picker