Remove Current Page drawer item
Replace gesture back/forward with toolbar buttons

Remove the swipe gesture back and forward buttons and use more
traditional toolbar back and forward buttons instead. Page views
can overflow, preventing horizontal swipe gestures being
recognized, and this is also consistent with external web view
back/forward.
Prevent back nav after clearing history

Because history is cleared asynchronously, after clearing history
PageViewController's back button state was not updated.
To fix, rather than fetching history to get the count of items,
keep a counter and update it when history is updated, setting to 0
on history clear.
Update history count on loading new page
Create settings controller

Create empty settings view controller
Remove duplicates from filtered search history

Use a mutable ordered set to store the previous searches filtered
by current search text so that duplicates aren't shown.
Hook up settings clear search history
Show arrow to select search suggestion

Show an arrow next to each search suggestion which will insert
the suggestion into the search field.
Fix #2 - fullscreen toggle shows above toolbar

Fix #2, a bug where the fullscreen toggle button appears above the
toolbar on app load in non-fullscreen mode, where it should only
show in fullscreen mode with the toolbar hidden.