Verify that vocabulary file is readable before import.
Append webfonts stylesheet to minimal layout.
Add wrapping divs to install form.
Remove time duration from installation manager. Catch exceptions when performing a task.
Add is unique validations to entity adapters
Add tab switching interaction, correct active section tab selector, flesh out vocabularies/show view.
Remove vocabulary check during validation.

When classes and properties are added during vocabulary hydration, they are validated without a vocabulary, so any check to see if the vocabulary exists will fail.
Reintroduce vocabulary check during validation.

Sets vocabulary to resource class and property entities prior to hydration, allowing vocabulary checks and is unique checks for existing vocabularies.
Validate uniqueness of class/property local name

When hydrating a vocabulary, checks that all associated resource class and property local names are unique.
Do not use method return value in empty()
Merge branch 'develop' into item-add

Conflicts:
	application/Omeka/src/Omeka/Api/Representation/Entity/VocabularyRepresentation.php
generalize add new value mechanism for both clicking the icon, and adding new of same property