Adjust vertical placement of drag handle indicator
Remove page options for curation item panels and adjust layout
Adjust layout of exhibit-specific fields table
Adjust layout and styling of browse category items
Merge pull request #611 from sul-dlss/improve-page-item-layout

Remove page options and improve layout and styling of curation pages
Abstract navigation configuration into a related model.
Use main navigation configuration to render the exhibit navbar.
Add configured label to breadcrumbs and sidebars.