Improve searching for a drug

[tamslo]

The content should not move with the keyboard to not hide more content than necessary (already implemented on login page).

• Hide button on initial drug selection page
• Hide "*" description in drug list (selection and search)
• One tester complained that the keyboard pops up every time the medications tab is opened, this should not happen
• Show navigation over keyboard (I hope this was only a problem because the keyboard was not easily dismissable – if showing the navigation above the keyboard, it will take too much space away from the content, so not implementing this for now)
• Make keyboard easier to hide

Also would be great to add "back to top button" (especially for drug selection as staying in "all" list)