Enhancement: Roles added to some elements to improve accessibility

Roles have been added to specific elements within the following views: Toolbar, Spaces, Drawer Menu, Manage accounts and Floating Action Button.
Improved the navigation system within the passcode view.

https://github.com/owncloud/android/issues/4373
https://github.com/owncloud/android/pull/4454
https://github.com/owncloud/android/pull/4466
